BCI 2022 Paper Solution

[ Option A ]

Memory storage refers to devices or media used to store data and programs in a computer.

• Primary memory (Volatile) is directly accessible by the CPU and loses its data when the power is turned off, examples include RAM and cache. 
• Secondary memory (Non-Volatile) stores data permanently, such as hard disks, SSDs, and optical discs.
• Tertiary and offline storage is used for backups and large-scale data storage, including tape drives and external hard drives.

Storage units are used to measure the amount of data in a computer, starting from the smallest unit, a bit, to larger units like Byte, Kilobyte (KB), Megabyte (MB), Gigabyte (GB), and Terabyte (TB).

• Bit → Byte → KB → MB → GB → TB → PB → EB → ZB → YB. Trick “Bharat Ke Modi Gaye Taj Pe Ek Zaruri Yatra”.

[ Option D ]

The program is trying to reduce the numbers p and q by repeatedly subtracting the smaller one from the bigger one. This looks like the Euclidean method for finding the GCD, but there is a mistake in the loop condition. The loop only checks while(p != 0), so it keeps running as long as p is not zero.

When q becomes zero (which will always happen before p does), the subtraction stops changing the value of p because p = p - 0 will always give the same p. This means the program gets stuck, and the loop keeps running forever without ending.

So, instead of calculating the GCD, this program will go into an infinite loop. The correct way would be to stop when either p or q becomes zero, i.e., use while(p != 0 && q != 0).
 

[ Option C ]

A Race Condition occurs when two or more threads or processes try to access and modify the same shared resource (like an object) at the same time without proper synchronization. This leads to unpredictable and incorrect behavior.
For instance, if three threads attempt to share and modify a single object concurrently, and there is no mechanism to control access (like locks or mutex), a race condition occurs causing data corruption or inconsistent results.

[ Option B ]

Phreaking is an early phone hacking method from the 1960s and 70s where hackers used special sounds to trick telephone systems. They played a 2600 Hz tone to control the phone switches and make free long-distance calls. Tools called "blue boxes" were made to create these tones, and famous phreakers like John Draper (“Captain Crunch”) used a cereal box whistle that made the same tone.

[ Option D ]

A Decision Table is a tabular method for representing logical relationships between conditions and actions in a system. It is widely used in software testing, system design, and decision-making.

[ Option D ]

Audio file formats are specialized file types designed to store or manage sound data.

• The .wav extension stands for Waveform Audio File Format, developed by Microsoft and IBM, and is commonly used for storing uncompressed, high-quality audio. 
• The .mp3 format, created by the Moving Picture Experts Group (MPEG), is a widely popular lossy compression standard, ideal for music, podcasts, and online streaming due to its smaller file size. 
• The .mid extension refers to MIDI (Musical Instrument Digital Interface) files, which do not contain actual sound but instead store digital instructions that control musical instruments, making them widely used in music production.
• In contrast, .rar is not an audio format. It is a Roshal Archive (RAR) file used for compressing and bundling multiple files together, unrelated to audio storage or playback.

[ Option C ]

WiFi and WiMAX are two popular wireless communication technologies, but they differ in coverage and standards. WiFi, based on the IEEE 802.11 family of standards, is mainly used for creating local area wireless networks with coverage typically up to 100 meters.

On the other hand, WiMAX is defined under the IEEE 802.16 standard and is designed for broadband wireless access over much larger distances, covering up to several kilometers.

The IEEE stands for Institute of Electrical and Electronics Engineers. IEEE develops global standards and supports a large community of engineers and scientists worldwide.

• 802.3 : Ethernet (Wired LAN standard, Data Link & Physical Layer).
• IEEE 802.5 : Token Ring LAN.
• 802.11 : WiFi (Wireless LAN).
• 802.15 : Wireless Personal Area Network (WPAN, Bluetooth).
• 802.16 : WiMAX (Worldwide Interoperability for Microwave Access, Broadband Wireless Access).
• IEEE 1394 : FireWire (High-speed serial bus for multimedia devices).

[ Option B ]

Snipping Tool / Snip & Sketch in Windows allows you to capture screenshots of a specific area, window, or full screen. Pressing Windows Key + Shift + S opens the screen snipping menu, letting you select a rectangular area, freeform area, window, or full screen. After selection, the screenshot is copied to the clipboard, and you can paste it into apps like Paint, Word, or email.

[ Option C ]

In C programming, floating point data types are used to represent real numbers, numbers that have fractional parts or decimals points.

• float
• double
• long double

#include <stdio.h>
#include <float.h>
void main()
{
    printf("Suraku Academy\n");
    printf("Size of float : %zu Bytes\n", sizeof(float));
    printf("Size of double : %zu Bytes\n", sizeof(double));
    printf("Size of long double : %zu Bytes\n", sizeof(long double));
    printf("Range and Precision:\n");
    printf("Float: Min : %e, Max : %e, Precision : %d Digits\n",FLT_MIN, FLT_MAX, FLT_DIG);
    printf("Double: Min : %e, Max : %e, Precision : %d Digits\n",DBL_MIN, DBL_MAX, DBL_DIG);
    printf("Long Double: Min : %Le, Max : %Le, Precision : %d digits\n",LDBL_MIN, LDBL_MAX, LDBL_DIG);
}

Output

Suraku Academy
Size of float : 4 Bytes
Size of double : 8 Bytes
Size of long double : 16 Bytes
Range and Precision:
Float: Min : 1.175494e-38, Max : 3.402823e+38, Precision : 6 Digits
Double: Min : 2.225074e-308, Max : 1.797693e+308, Precision : 15 Digits
Long Double: Min : 3.362103e-4932, Max : 1.189731e+4932, Precision : 18 digits

• In C, the format specifier %zu is used to printing results of sizeof or variables declared as size_t type. The sizeof operator returned size_t which is an unsigned integer type.
• In C, the format specifier %e is used for prints floating point numbers (float, double, long double) in scientific (exponential) notation.

[ Option C ]

System Software is the type of software that manages computer hardware and provides a platform for running application software. Common examples of system software include the Operating System (OS), utility programs, and language translators such as compilers, interpreters, and assemblers.

Application Software is designed to help users perform specific tasks or solve particular problems. It runs on top of system software and allows users to do activities like creating documents, managing databases, browsing the internet, or editing images. Examples include word processors, spreadsheet software, Database Management Systems (DBMS) software, and web browsers.

Utility Programs are System Software tools that help maintain, manage, and protect a computer. Examples include Antivirus Software for security, Disk Cleanup tools for removing unnecessary files, file compression software like WinRAR (Windows Roshal ARchive) or 7-Zip for reducing file size, backup software for data safety, and disk defragmenters for improving storage performance.

• A Database Management System (DBMS), such as MySQL, Oracle, Microsoft SQL Server, or MS Access, is an application software that allows users to store, organize, retrieve, and manage data efficiently.

[ DELETE ]

The statement (i) is correct because if a subclass does not implement all abstract methods, it must also be declared abstract. Otherwise, there will be compile time error.

abstract class Person {
    abstract void setName(); // abstract method
}
// Subclass does not implement setName(), so it must also be abstract
abstract class Student extends Person {
    // no setName() defined here
}
// If we try to make Student concrete without implementing setName(), error occurs, Student is not abstract and does not override abstract method setName() in Person
class MainClass {
    public static void main(String[] args) {
        System.out.println("Suraku Academy Program");
    }
}

The statement (ii) is incorrect because abstract classes can have constructors and static methods. The constructors are called when concrete subclasses are instantiated, and static methods do not require object instantiation.

abstract class Person {
    Person(){ //Constructor
        System.out.println("Person Constructor.");
    }
    static void staticMethod() { // Static method
        System.out.println("Static method in abstract class Person");
    }
}
// Subclass does not implement setName(), so it must also be abstract
class Student extends Person {
    Student() {
        super();
    }
}
class MainClass {
    public static void main(String[] args) {
        System.out.println("Suraku Academy Program.");
        Person.staticMethod();
        Student s1 = new Student();
    }
}

Output
Suraku Academy Program.
Static method in abstract class Person
Person Constructor.

The statement (iii) is incorrect because we cannot create object of an abstract class directly.

abstract class Person {
}
class Main {
    public static void main(String[] args) {
        System.out.println("Suraku Academy Program.");
        Person p1 = new Person(); //Error: Person is abstract; cannot be instantiated.
    }
}

The statement (iv) is incorrect because only abstract methods need to be redefined. But an abstract class can also have concrete methods (method with body), and those need not be redefined.

In another aspect, only concrete subclasses (non-abstract class) must implement all abstract methods. An abstract subclass does not have to reimplement inherited abstract methods. Redefinition is only mandatory in a concrete class.

abstract class Person {
    abstract void setName();
}
abstract class Student extends Person {
    // Does not implement 'setName()', so must remain abstract.
}
class Employee extends Person {
    void setName() {
        System.out.println("Setting Name.");
    }
}

We carefully discussed this question and observed that statement (i) is correct, while statements (ii), (iii), and (iv) are incorrect. The question required us to identify the incorrect statements, but none of the provided options matched the correct combination.

Additionally, there were duplicate/confusing options such as (b) (ii) and (iii), and (c) (ii) and (iv). Due to this ambiguity in the answer choices, this question was removed from the final answer key.

[ Option D ]

The error in this SQL statement occurs because the FROM clause is missing, which is required to specify the table from which data should be retrieved. A correct SELECT query must always include the FROM keyword followed by the table name. Additionally, if a column name contains spaces (for example, last name), it should be enclosed in quotes or brackets to avoid syntax errors.

[ Option B ]

Computer generations are classified based on the technology used in their hardware. Each generation shows significant improvements in speed, size, reliability, and efficiency over the previous one. They also differ in the type of memory, input/output devices, and programming languages used, reflecting the evolution of computing technology over time.

Must Know:

• ENIAC: Electronic Numerical Integrator and Computer, developed in 1945, was the first general-purpose electronic computer.
• UNIVAC I: Universal Automatic Computer I, introduced in 1951, was the first commercially produced digital computer in the U.S.
• IBM 701: International Business Machines 701, released in 1952, was IBM's first commercial scientific computer. 
• EDVAC: Electronic Discrete Variable Automatic Computer, completed in 1951, was one of the earliest electronic computers.
• EDSAC: Electronic Delay Storage Automatic Calculator.
• IBM 1401: Introduced in 1959, was a transistorized computer system used for business data processing.
• CDC 1604: Developed in 1958, was one of the first commercially successful transistorized computers.
• PDP-8: Released in 1965, was the first commercially successful minicomputer, using integrated circuits.
• PDP-11: Introduced in 1970, was a series of 16-bit minicomputers using integrated circuits.
• Intel 8086: Introduced in 1978, was a 16-bit microprocessor, marking the beginning of the x86 architecture.
• IBM PC: Introduced in 1981, was a personal computer based on the Intel 8088 microprocessor.
• Apple II: Released in 1977, was one of the first pre-assembled personal computers.

[ Option A ]

Aircrack-ng is a widely used toolset for Wi-Fi hacking and security testing. It includes tools for capturing network traffic, testing wireless card capabilities, and cracking WEP (Wired Equivalent Privacy), WPA (Wi-Fi Protected Access), and WPA2 encryption keys.

It supports various attacks such as deauthentication and replay attacks to capture handshake data needed for cracking passwords. This tool is popular among security professionals and hackers for analyzing and testing Wi-Fi network security.

Wireshark is a powerful packet analyzer useful for inspecting network traffic and can assist in wireless troubleshooting or analysis, but it is not primarily a Wi-Fi cracking tool.

[ Option D ]

Cache memory is a small, high-speed storage area located between the CPU and the main memory (RAM). Its primary function is to store copies of frequently accessed data and instructions, enabling the CPU to retrieve them more quickly than if it had to access the slower main memory every time.

1.    L1 Cache (Level 1)

• Located inside the CPU.
• Very fast but small in size (usually 16 KB – 128 KB).
• Stores instructions and data frequently used by the CPU.

2.    L2 Cache (Level 2)

• Located on the CPU chip or close to it.
• Larger than L1 (usually 128 KB – 8 MB).
• Acts as a secondary buffer between CPU and RAM.

3.    L3 Cache (Level 3)

• Shared among all CPU cores.
• Larger but slightly slower than L2.
• Enhances multi-core processor performance by sharing data across cores.

UVEPROM (Erasable Programmable Read-Only Memory), used for storing firmware. It can be erased with UV light and reprogrammed multiple times.

Flash Memory, it is non-volatile storage used in USB drives, SSDs, and memory cards. It retains data without power and allows fast read and write operations.

DVD (Digital Versatile Disc), optical storage media for large data, very slow compared to CPU. It is commonly used for movies, software distribution, and backup purposes.

[ Option B ]

[ Option B ]

A bootstrap loader is a small program that starts the process of loading the operating system (OS) when a computer is powered on. It is stored in ROM (Read-Only Memory) because ROM is non-volatile, meaning its contents are retained even when the computer is turned off.

[ Option C ]

Schema change statements in SQL are used to modify the structure of existing database objects like tables, columns, or constraints. These changes can include adding or removing tables, columns, or other schema elements. The most common schema change statements are DROP and ALTER.

• The DROP statement is used to delete schema elements, such as tables or columns, from the database. It can remove an entire schema or individual database objects.
• The ALTER statement is used to modify the structure of existing objects, like adding or dropping columns, modifying column data types, or renaming columns. ALTER allows database schemas to evolve over time without losing data.

[ Option C ]

A view in a database is a virtual table that represents the data retrieved by a stored SQL query from one or more base tables. 

Unlike base tables and indexes, which physically exist and store data on disk, a view does not store data itself. Instead, it holds only the SQL query defining it. 

When a user queries the view, the database engine executes the stored query dynamically on the underlying base tables to fetch the current data. This allows views to provide a customized and simplified representation of data, enforce security by controlling data access, and reduce complexity without duplicating storage. 

Views serve as logical abstractions that help organize and present data efficiently without physically occupying storage space.

[ Option D ]

In MS Excel, the LCM function is used to calculate the Least Common Multiple of one or more numbers. The LCM is the smallest number that is divisible by all the given numbers with remainder 0. For example, the formula =LCM(5, 7, 35) calculates the LCM of 5, 7, and 35.

[ Option B ]

In Excel 2016, when you want to insert multiple columns, it is important to understand that Excel always inserts new columns to the left of the selected column(s). 

To insert 3 columns between Column G and H, we need to select Column H first. By right-clicking and choosing Insert, a new column will appear to the left of H. Repeating this process three times will insert three new columns exactly between G and H.

[ Option C ]

To evaluate a prefix expression, also known as Polish notation, the operator precedes its operands. The evaluation process involves scanning the expression from right to left. When an operand is encountered, it is pushed onto a stack. When an operator is found, the two most recent operands are popped from the stack, the operator is applied to these operands, and the result is pushed back onto the stack.

This continues until the entire expression has been scanned. The final result of the expression is the sole remaining value on the stack.

[ DELETE ]

Most likely, the question was deleted due to ambiguity in font classification and potential for confusion.

[ Option D ]

In Java, the final keyword is used to restrict modification and ensure immutability where needed. A method declared as final cannot be overridden in subclasses, which helps in maintaining consistent behavior.

class Parent {
    final void show() {
        System.out.println("This is a final method");
    }
}
class Child extends Parent {
    void show() {}  // Compile-Time Error.
}

A class declared as final cannot be inherited, which is useful for creating immutable classes or preventing extension.

final class MyClass {
    int value = 100;
}

class NewClass extends MyClass { }  //Compile-Time Error.

If a variable is declared final, its value cannot be changed, regardless of whether it is inside a final method.

final int p = 33;
final void modifyValue() {
    p = 20; //Compile-Time Error.
}

The finalize() method in Java is a special method of the Object class that is called by the garbage collector before an object is removed from memory. It can be used to perform cleanup tasks, such as closing file streams, releasing network connections, or freeing other system resources held by the object.

class MyClass {
    protected void finalize()throws Throwable {
        System.out.println("Object is being Garbage Collected");
    }
}

[ Option C ]

A Computer Virus is a type of malicious software that attaches itself to files or programs and can spread from one system to another. Just like a biological virus, it has a life cycle made up of different stages.

[ Option B ]

In Microsoft PowerPoint 2016, the Master Views allow users to control the overall look, layout, and formatting of slides, handouts, and notes in a presentation. The main Master View options are:
Slide Master: This is the primary master that controls the design, layout, fonts, colors, and placeholders for all slides in the presentation. Any changes made here automatically apply to all associated slides.
Handout Master: This master controls the appearance and layout of printed handouts, including the number of slides per page, headers, footers, and page orientation.
Notes Master: This master is used to format the notes pages, which include slide thumbnails and speaker notes. It allows customization of fonts, colors, and layout for printing or viewing.

[ Option D ]

A SPOOLER is special system software used to manage and create a job queue. It stands for Simultaneous Peripheral Operations On-Line. The spooler collects jobs  and stores them in a queue (FIFO), then executes them one by one in order, ensuring efficient use of resources. The spooler ensures jobs are executed in the correct order without conflicts or loss.

[ Option A ]

SMTP (Simple Mail Transfer Protocol) is the protocol used to transfer email messages from the sender's mail server to the recipient's mail server across the internet. It is an application layer protocol that uses TCP to reliably send and relay email messages between servers until reaching the destination server.

• SMTP takes care of the sending and forwarding of emails across networks but does not handle retrieving or storing emails on client devices.

The IMAP (Internet Message Access Protocol) and POP (Post Office Protocol) are involved in email retrieval from mail servers to client devices, not in sending emails through the internet. UDP (User Datagram Protocol) is a transport protocol used for fast, connectionless communication. 

[ Option C ]

XML (Extensible Markup Language) is designed to organize and store data in a clear, hierarchical structure. It allows creating custom tags to describe the data, making it easy for both humans and machines to understand. XML is especially useful for managing complex information where the relationships between data need to be clearly shown.

Unlike HTML (Hypertext Markup Language), which is mainly used to display content on web pages, XML focuses on transporting and storing data rather than how it looks. XML is often used in documents, configuration files, and web services where data needs to be shared or transferred between different systems in an organized way. This separation of data and presentation helps keep information consistent and easy to update.

[ Option B ]

In Java, constants that cannot be changed are declared using final, often combined with static for class-level constants, example, static final int P = 33;. Simply using static does not make a variable constant.

Java supports single inheritance for classes, meaning a class can extend only one superclass. However, a class can implement multiple interfaces, allowing it to inherit behavior from multiple sources like multiple inheritance.

class Super {}
interface A {}
interface B {}
class Sub extends Super implements A, B
{
}

[ Option A ]

SD (Secure Digital, launch in the year 1999 by Panasonic, Toshiba, SanDisk), a type of non-volatile memory card used in cameras, mobiles, laptops, etc. The term "Secure Digital" refers to the original purpose, providing secure, portable storage for digital devices.

MMC (Multimedia Card, launch in the year 1997 by Siemens & SanDisk), an older memory card standard developed before SD cards. These are similar in size, but slower and less secure compared to SD.

• SD stands for Secure Digital, which is modern, secure, and widely used in devices like cameras, smartphones, and laptops. On the other hand, MMC stands for Multimedia Card, which is an older standard with limited speed and storage, and is now mostly replaced by SD cards.

[ Option A ]

To quickly convert a number from octal to hexadecimal, first convert the octal number into binary by replacing each octal digit with its 3-bit binary equivalent. Then, group the binary digits into 4-bit groups starting from the right. Finally, convert each 4-bit group into its hexadecimal equivalent. 
For example, to convert 356₈to hexadecimal:

• Convert each octal digit to 3-bit binary: 3 → 011, 5 → 101, 6 → 110 → 011101110₂
• Group into 4-bit sections from the right: 1110 1110₂
• Convert each group to hexadecimal: 1110 → E, 1110 → E → EE₁₆

So, 356₈ = EE₁₆.

[ Option C ]

An aggregate function in SQL performs a calculation on a set of values and returns a single summarized result. These functions are commonly used to analyze and summarize data, especially when combined with the GROUP BY clause. The aggregate functions include:

• COUNT, which counts the number of rows.
• SUM, which adds up numeric values.
• AVG, which calculates the average.
• MIN, which find the smallest value.
• MAX, which find the largest value.

Aggregate functions help in generating reports, insights, and statistical summaries from large datasets efficiently.

[ Option B ]

A relation is in Third Normal Form (3NF) if:

• It is in Second Normal Form (2NF).
• Every non-key attribute is fully functionally dependent on the primary key.
• It has no transitive dependencies — meaning no non-key attribute depends on another non-key attribute.

This means each non-key attribute depends only on the primary key and not on other non-key attributes, which helps eliminate redundancy and update anomalies.

[ Option A ]

(i) There can be try block without catch block but vice versa is not possible.

• In Java, a try block must always be followed by either a catch block or a finally block. But you cannot have a catch block without a try. So, this statement is true.

(ii) There is no limit on the number of catch blocks corresponding to a try block.

• In Java, you can write multiple catch blocks after a single try block to handle different types of exceptions. There is no restriction on the number of catch blocks. So, this statement is true.

(iii) The object must be created of a specific class of which the error has occurred otherwise runtime error will occur.

• In Java, when an exception occurs, the JVM automatically creates an exception object of the corresponding class and throws it. You do not need to manually create the object. So, this statement is false.

(iv) To execute a code with each and every run of program, the code is written in finally block.

• The finally block in Java is always executed, whether an exception is thrown or not. It is generally used for cleanup code like closing files, releasing resources, etc. So, this statement is true.

public class ExceptionExample {
    public static void main(String[] args) {
        try 
        {
            int a = 10;
            int b = 0;
            int c = a / b;
            System.out.println("Result: " + c);
        } 
        catch (ArithmeticException e) 
        {
            System.out.println("Error: Cannot divide by zero!");
        } 
        catch (NullPointerException e) 
        {
            System.out.println("Error: Null value encountered!");
        } 
        finally 
        {
            System.out.println("Finally block: This will always execute.");
        }
        System.out.println("Program continues after exception handling.");
    }
}

[ Option C ]

In MS Word, a gutter is extra space added to the margin of a document to allow for binding, such as in books, reports, or manuals. It ensures that text does not get hidden in the spine or fold of the bound document.

[ Option B ]

[ Option A ]

The input array is 32, 51, 27, 85, 66, 23, 13, 57. In bubble sort, we compare adjacent elements and swap them if the left element is greater than the right. During the first pass, the largest element moves to the last position.

During first pass, compare 32 and 51 → no swap, 51 and 27 → swap, 51 and 85 → no swap, 85 and 66 → swap, 85 and 23 → swap, 85 and 13 → swap, and 85 and 57 → swap. After completing these comparisons and swaps, the array becomes 32, 27, 51, 66, 23, 13, 57, 85.

[ DELETE ]

Before understanding why this question was deleted in the BCI Exam 2022, we need to study the concept behind it. The question involved the use of increment (++) / decrement (--) operators with the dereference (*) operator in C/C++. Since operator precedence and associativity decide whether the pointer moves or the value changes, such expressions become tricky and ambiguous, which often leads to confusion in exams.

To fully grasp the essence of this question and to understand the concept clearly, please read this blog attentively. This will provide you with a comprehensive explanation and deeper insight into the topic.

[ Option D ]

[ Option D ]

NoSQL (Not Only SQL) databases are non-relational databases designed to handle large volumes of unstructured or semi-structured data. They are categorized into different types based on their data models: document-based, key-value, column-family, and graph databases.

• JSON (JavaScript Object Notation) is a lightweight, text-based data format used to store and exchange data. It represents data as key-value pairs organized in objects and arrays, making it easy for humans to read and write, and for machines to parse and generate. 
• JSON is widely used in web applications to transfer data between clients and servers. In NoSQL databases, JSON is often the native format for storing data.

[ Option A ]

In Java, strings can be created in two ways. The first method is by using string literals, for example: String s = "Hello Java";. In this case, the string is stored in the String Constant Pool (SCP), which allows Java to reuse memory efficiently.

The second method is by using the new keyword, for example: String s2 = new String("Hello Java");. This approach creates a new String object in heap memory, separate from the SCP, even if an identical string already exists in the pool.

However, in the given question, option (ii) is written as String S2 = New string("Hello Java");. This is incorrect due to Java’s case sensitivity:

• New should be new (lowercase).
• string should be String (uppercase S).

Because of these errors, option (ii) will cause a Compile-Time Error (CTE), and only option (i) is valid as written.

[ Option D ]

In a Relational Database Management System (RDBMS), keys are used to uniquely identify records in a table or relation. A super key is an attribute or a combination of attributes that ensures the uniqueness of each record. Among these super keys, a candidate key is a minimal set of attributes that can still uniquely identify a record, meaning it does not contain any unnecessary attributes.

In other words, every candidate key is a subset of a super key, but not all super keys are candidate keys because some may include extra attributes that are not needed for uniqueness.

[ Option D ]

A software process model is a structured approach that defines the sequence of steps or phases to be followed for systematic software development.

The COCOMO (Constructive Cost Model) is a well-known software cost estimation model developed by Barry W. Boehm in the late 1970s. It helps predict the amount of effort, time, and resources required to complete a software development project based on software size, usually measured in lines of code (LOC).

[ Option A ]

Cryptography, the science of securing communication by using encryption and decryption techniques.

The information that gets transformed during encryption is called Plain Text. Plain text refers to the original, human-readable data such as messages, files, or any sensitive information.

Encryption is the process of converting readable information, called plain text, into an unreadable or scrambled format known as Cipher Text, using algorithms and cryptographic keys. The Cipher Text, ensures that unauthorized users cannot understand it without the proper key.

Decryption is the reverse of encryption. It transforms encrypted data (cipher text) back into its original readable form (plain text) using a decryption key.

[ Option C ]

The given infix expression is a + (b/c) * (d^e) - f. To convert it into prefix form, we first look at the inner brackets. The term (b/c) in prefix becomes / b c, and the term (d^e) becomes ^ d e.

Next, these two are multiplied, so (b/c) * (d^e) becomes * / b c ^ d e. Now, this result is added to a, so the expression a + ((b/c) * (d^e)) becomes + a * / b c ^ d e. Finally, we subtract f from this whole result, so the complete prefix form becomes - + a * / b c ^ d e f.

[ Option C ]

A super key is a set of one or more attributes that uniquely identify each record in a table. However, a super key may include extra attributes that are not necessary for uniqueness.

When we remove all unnecessary attributes from a super key, leaving the minimal set of attributes that still uniquely identify each record, it becomes a candidate key.

Every candidate key is a minimal super key, meaning it cannot be reduced any further without losing the ability to uniquely identify records. From among the candidate keys, one is selected as the primary key to uniquely identify rows in the table.

[ Option D ]

[ Option A ]

[ Option D ]

In the given stack implementation, the size of the array is defined as 11, which means the stack can hold elements from index 0 to 10. Initially, the value of top is -1, and each time an element is pushed, the value of top increases by one.

When the stack is completely filled, the top will point to the last valid index, which is 10. At this stage, the stack contains 11 elements in total, and if we try to push one more element, it will cause an overflow. Therefore, the maximum value of top that does not cause overflow is 10.

[ Option A ]

Gorilla Testing is a software testing technique that focuses heavily on testing a specific module or feature of an application. It involves intense, repetitive, and rigorous testing of one particular part to find as many defects as possible in that area. This method ensures the robustness and reliability of critical modules, uncovering hidden bugs that might be missed in broader testing.

Fuzz Testing involves providing random or invalid inputs to the software to check how it handles unexpected data.

Inter-System Testing, tests the interaction between two or more different systems to ensure they work together correctly.

Breadth Testing, focuses on testing all modules at a shallow level without going deep into any single one.

[ Option B ]

A super key is any set of attributes that contains the primary key or a superset of it. Since the primary key is VY, any super key must at least include both attributes V and Y.

(a)  VXYZ: Has V,X,Y,Z. It contains both V and Y. So, this is a super key.
(b)  VWXZ: Has V,W,X,Z. It contains V but does not have Y. So, this is not a super key.
(c)  VWXY: Has V,W,X,Y. It contains both V and Y. So, this is a super key.
(d)  VWXYZ: Has V,W,X,Y,Z. It contains both V and Y. So, this is a super key.

[ Option D ]

Animation formats are special file types or containers made to store moving images or animated sequences. FLI and FLC are examples of animation file formats created by Autodesk for frame-based animations. MPEG (Moving Picture Experts Group) (MPEG files usually have extensions like .mpg, .mpeg, .mp4) is a widely used video format that supports motion content, while QuickTime (QT/Moov), developed by Apple, works as a multimedia container for both animations and videos.

On the other hand, SGI (Silicon Graphics Image) is not an animation format. It is an image file format designed for Silicon Graphics workstations and is mainly used for storing static raster images. Since it does not support animated or moving content, it cannot be considered an animation format like the others.

[ Option B ]

In Python, writing xyzp = 5,000,000 is syntactically correct, but it does not store the integer 5000000. Instead, Python treats the commas as separators and creates a tuple (5, 0, 0). If we want to store 5000000 in python variable then correct way is either xyzp = 5000000 or xyzp = 5_000_000 for readability.

The statement, x, y, z, p = 5000, 6000, 7000, 8000 uses tuple unpacking, assigning each number to a separate variable: x = 5000, y = 6000, z = 7000, and p = 8000. This is a valid and commonly used Python syntax.

The statement, x_y_z_p = 5,000,000, is similar to statement xyzp = 5,000,000. It is syntactically correct, and the variable name is valid, but the value becomes a tuple (5, 0, 0).

The statement, xyzp = 5000 6000 7000 8000, is completely invalid in Python. The numbers cannot be written separated by spaces, and this will throw a syntax error.

[ Option D ]

XML (eXtensible Markup Language) is a flexible, text-based markup language designed to store, organize, and transport structured data. It uses custom tags to represent information in a hierarchical format, making it both human-readable and machine-readable. XML is widely used in web applications, data exchange, configuration files, and document storage because it is platform-independent and supports integration across different systems.

[ Option D ]

Hacktivism is the combination of "hacking" and "activism." It refers to the act of breaking into computer systems or networks with the intention of promoting political or social causes (not for financial gain).
Hacktivists use hacking techniques to raise awareness, protest against injustices, or support specific movements by targeting organizations, governments, or corporations they oppose.
Common hacktivist activities include:

• Website defacements.
• Distributed Denial of Service (DDoS) attacks.
• Leaking confidential information to expose organizations or governments.

[ Option C ]

FTP (File Transfer Protocol) is used to transfer files between a client and a server on a network. In FTP, data can be transferred using different transmission modes that determine how the file data is sent over the connection.

• Stream Mode is the default mode where data is sent as a continuous stream of bytes without any additional processing until the end-of-file is reached. TCP ensures reliability.
• Block Mode transfers data in blocks, where each block contains a header that describes the block size and type. This is useful for structured data transfers.
• Compressed Mode compresses the data before transmission, reducing the size of the file to speed up transfer, usually using run-length encoding.
   

[ Option A ]

Software Testing is the process of evaluating a software application to check whether it meets the specified requirements and works as expected. It helps to identify defects, errors, or gaps so that they can be fixed before the product is delivered. The main goals of testing are:

• To ensure the software is reliable, accurate, and secure.
• To confirm it works correctly under different conditions.
• To improve the quality and user satisfaction of the final product.

After this, testing is usually carried out in different levels (Unit, Integration, System, Acceptance) to make sure the software is correct at every stage.

[ Option B ]

Information Gathering is the process of collecting facts, opinions, and requirements from stakeholders, users, or sources to understand a problem or design a system. It is a crucial step in software engineering, system analysis, and research because decisions made later depend on accurate and complete information. The main objectives are to:

• Understand user needs and expectations.
• Identify problems, constraints, and requirements.
• Collect reliable data for designing effective solutions.

In the context of information gathering, different types of questions are designed to capture different kinds of responses from participants:

[ Option B ]

A checksum is used in networking to verify data integrity. It works by adding binary values of data segments and sending the result with the packet. At the receiver’s end, the same calculation is done and compared. If they do not match, an error is detected. However, checksum only supports error detection, not correction.

[ Option D ]

In MS Word, a Bookmark is used to give a name to a specific place in a document. This makes it easy to jump to that spot quickly or link to it from another part of the document using a Hyperlink or Cross-Reference.

[ Option C ]

Relational algebra is a set of basic operations used to manipulate data in relational databases. These includes:

• The selection (σ), which filters rows based on conditions.
• The  projection (π), which chooses specific columns.
• The union (U), combining rows from two relations, removing duplicates.
• The set difference (−), finding rows present in one relation but not in another.
• The Cartesian product (×), pairing rows from two relations.
• The rename (ρ), which changes relation or column names.

These operations take relations as input and produce new relations as output, forming the foundation for querying data efficiently and systematically.

[ Option A ]

[ Option C ]

[ Option D ]

In an Operating System (OS), a process is a program in execution. Each process moves through various states during its life cycle, from creation to termination. Typically, a process can exist in five main states.

[ Option C ]

[ Option C ]

Unary operators operate on a single relation (table) and produce a relation as output.

• Select (σ): Retrieves tuples (rows) from a relation that satisfy a specified condition. It filters rows based on predicates.
• Project (π): Extracts specified columns (attributes) from a relation, removing duplicates by default.
• Rename (ρ): Renames a relation or its attributes. Useful for clarity or avoiding conflicts in operations.

Binary operators work on two relations (tables) and produce a new relation as output.

• Union (∪): Combines tuples from two relations, removing duplicates. Both relations must have the same schema.
• Set Difference (-): Returns tuples present in the first relation but not in the second.
• Cartesian Product (×): Combines tuples from two relations in every possible pair, creating a relation with all attributes of both.
• Join (⋈): Combines related tuples from two relations based on a condition, essentially a filtered cartesian product.

[ Option A ]

In a tree data structure, there are three primary types of traversal sequences used to visit all the nodes systematically: Preorder, Inorder, and Postorder traversal.

1. Preorder traversal visits nodes in the order: root first, then the left subtree, followed by the right subtree. This means the current node is processed before its child nodes.
2. Inorder traversal visits nodes by first traversing the left subtree, then the root node, and finally the right subtree. This order is commonly used in binary search trees because it visits nodes in ascending sorted order.
3. Postorder traversal visits the nodes by first traversing the left subtree, then the right subtree, and finally the root node. This traversal is especially useful when deleting trees or evaluating postfix expressions.

So,

(1) Preorder Traversal: Root → Left → Right
(2) Inorder Traversal: Left → Root → Right
(3) Postorder Traversal: Left → Right → Root

The preorder traversal of the tree is ABCDEF, which means the root of the tree is A. Looking at the inorder traversal BADCFE, we see that A splits the tree into a left subtree (B) and a right subtree (DCFE). Thus, B is the left child of A, and the rest of the nodes (DCFE) belong to the right subtree.

In the right subtree, the preorder sequence is CDEF, so the root here is C. From the inorder sequence DCFE, the node C splits the subtree into D on the left and FE on the right. For the FE part, preorder tells us the root is E, and inorder (FE) shows that F is on the left of E. This gives the right subtree structure: C has left child D and right child E, with E having left child F.

Now, constructing the postorder traversal: start with the left subtree of A which is B, then the right subtree rooted at C. For C, its left subtree gives D, and its right subtree rooted at E gives F followed by E. After these, we add the root C. Finally, we append the overall root A. Putting this together, the Postorder is B D F E C A.

[ Option B ]

In a Data Flow Diagram (DFD), a Black Hole is a process or data store that receives data but does not produce any output. In other words, information flows into it, but nothing comes out. This situation usually indicates an error or a missing component in the diagram, as every process should normally transform or pass on data through both input and output flows.

Apart from a Black Hole, there are several other common errors in Data Flow Diagrams (DFD):

[ Option B ]

[ Option C ]

A printer is an output device that produces a hard copy of text, images, or graphics from a computer or other digital devices. Printers are classified based on the mechanism used to print, speed, and quality of output.

1. Impact Printers, print by physically striking an ink ribbon against the paper.
2. Non-Impact Printers, print without physically striking the paper, using heat, laser, or ink.
3. 3D Printers, create three-dimensional objects by layering material according to a digital model.
4. Multifunction Printers (MFPs), combine printing, scanning, copying, and sometimes faxing into a single device.

[ Option A ]

In MS Excel, several tools are used for What-If Analysis, which helps in forecasting and decision-making. Tools like Scenario Manager, Goal Seek, and Data Table allow users to analyze different input values and see their impact on results. On the other hand, Portrait refers to the page orientation in the Page Layout settings and has nothing to do with data analysis or forecasting.

[ Option B ]

In MS Word, decorative or stylized text that is used to make headings or titles visually attractive is called WordArt. WordArt allows you to apply special effects, colors, and shapes to text to make it stand out in a document.

[ Option B ]

In a system study project, the very first step is to describe the information needs of users and the organization. This step is crucial because it helps in identifying what data is required, how it should be processed, and what outputs are necessary for decision-making.

Once the information needs are clearly understood, other steps such as defining system performance criteria, staffing for the study project, and officially announcing the project can be carried out effectively. Without properly identifying user requirements at the start, the system cannot be designed to meet organizational goals.

[ Option C ]

Statement I says that binary search is faster than linear search. This is true because binary search works by repeatedly dividing the sorted list in half, giving it a time complexity of O(log n), whereas linear search checks each element one by one and takes O(n) time.

Statement II says that binary search may not be applied on all the input lists on which linear search can be applied. This is also true because binary search requires the list to be sorted, while linear search works on both sorted and unsorted lists.

[ Option A ]

A Multiplexer (MUX) is a combinational logic circuit that selects one input from 2ⁿ input lines and forwards it to a single output line based on n select lines. It effectively channels multiple inputs into a single output line by selecting one input at a time.

[ Option B ]

Initially, the variables are a = 10, b = 5, and c = 10. The if statement checks the condition (a > b) && (a <= c). Evaluating step by step: a > b is 10 > 5, which is true, and a <= c is 10 <= 10, which is also true. Since both parts of the condition are true, the && operator makes the whole condition true. Therefore, the code inside the if block executes, which is a = a + 1, so a becomes 11. The else block does not execute, so c remains 10.

[ Option D ]

Password Cracking is the process of attempting to discover or recover a password to gain unauthorized or authorized access to a system, account, or network. It is performed either to recover forgotten passwords or, more maliciously, to break into systems by guessing the correct password.

Attackers use various automated tools and techniques to systematically guess or decrypt passwords by exploiting weak or commonly used ones.

1. Guessing, the attacker manually guesses passwords based on known information about the victim such as names, birthdays, or common passwords.
2. Brute Force Attack, this method tries every possible combination of characters until the correct password is found. It is simple but can be time-consuming, effective mostly against short or weak passwords.
3. Syllable Attack, a syllable (pronounceable) attack makes likely passwords by joining small, easy-to-say parts (syllables), the kind of words people choose because they are memorable. For example, it might try combinations like "pa" + "ss" + "word" is "password" or "su" + "ra" + "ku" is "suraku".
4. Dictionary Attack, it uses a precompiled list (dictionary) of common words, phrases, or known passwords to guess the correct password. This is faster than brute force if the password is common or predictable.
5. Hybrid Attack, it combines dictionary and brute force methods by using dictionary words with added numbers or symbols. This expands the guessing capability while focusing on likely password patterns.
6. Credential Stuffing, it utilizes leaked username-password pairs from previous breaches to try and gain unauthorized access to accounts where users reuse passwords across sites.
7. Rainbow Table Attack, it uses precomputed tables of hashed passwords to reverse the hashing process and find the original password quickly, especially if weak or unsalted hashes are used.

[ Option C ]

In computer networks, binary data cannot always be transmitted directly over text-based protocols like email (SMTP) or web (HTTP). To solve this problem, Base64 encoding is used. Base64 takes every 24 bits of input data (3 bytes) and divides it into four groups of 6 bits each. Each 6-bit value is then mapped to a printable ASCII character.

Since each Base64 output is an ASCII character, it requires 8 bits of storage. Therefore, four characters × 8 bits = 32 bits of output are generated from the original 24 bits. This explains why Base64 increases the size of the encoded data by about 33%.

When encoding the string "SRK" into Base64, the process begins by converting each character into its ASCII binary form. The character S has an ASCII value of 83, which is 01010011 in binary. The character R has an ASCII value of 82, represented as 01010010. Finally, the character K has an ASCII value of 75, represented as 01001011. Together, the string "SRK" produces a 24-bit binary stream:

01010011 01010010 01001011

Next, these 24 bits are divided into groups of 6 bits each:

010100 110101 001001 001011

Each 6-bit group is then converted into its decimal equivalent:

• 010100 = 20
• 110101 = 53
• 001001 = 9
• 001011 = 11

Using the Base64 index table, these decimal values are mapped to their respective characters:

• 20 = U
• 53 = 1
• 9 = J
• 11 = L

Thus, the final Base64 encoded output of the string "SRK" is: U1JL

[ Option A ]

In a Relational Database Management System (RDBMS), a materialized view is a database object that stores the results of a query physically. Unlike a regular view, which calculates data only when it is accessed, a materialized view keeps the data ready in advance, which helps speed up complex queries.

Since the original tables can change with INSERT, UPDATE, or DELETE operations, the data in a materialized view can become outdated. To keep it current automatically, RDBMS uses triggers, which are special procedures that run whenever the underlying table data changes, ensuring the materialized view stays up-to-date.

• A trigger is a type of procedural code in a database that runs automatically in response to specific events on a table or view, such as INSERT, UPDATE, or DELETE operations. 
• Triggers help enforce business rules, maintain data integrity, and automate repetitive tasks without manual intervention.
• In the context of materialized views, when the underlying table data changes, a trigger can automatically refresh or update the materialized view. This ensures that the view always reflects the latest data, keeping it consistent with the base tables.
   

[ Option D ]

Software Complexity refers to the degree of difficulty in understanding, developing, testing, and maintaining a software system. A highly complex system usually has more lines of code, intricate logic, higher development effort, and is harder to manage. Measuring complexity helps in estimating cost, time, and resources needed for software projects.

Lines of Code (LOC): Counts the total number of lines in the source code. More lines usually mean more complexity, but it does not reflect code quality or logic.
Man-Years: Shows the total human effort (time and people) needed to build the software. Bigger and more complex projects require more man-years.
Function Points (FP): Measures the software based on the functionality it provides to users (inputs, outputs, files). Independent of programming language, it gives a better view of user-side complexity.
Cyclomatic Complexity: Measures how many independent paths exist in the program’s flow (like branches, loops, conditions). Higher values mean the program is harder to test and maintain.

[ Option D ]

An Artificial Intelligence (AI) agent is a computer program that can sense what is happening around it, make decisions, and take actions to reach goals. It works on its own without needing someone to tell it every step. AI agents learn from experience and can adapt to changes in their environment. They are used in many areas to help automate tasks and solve problems.

[ Option C ]

The SQL command DELETE FROM EMPLOYEE; without a WHERE clause will delete all tuples (rows) from the EMPLOYEE relation or table. It removes every record, but the table structure, columns, and schema remain intact.

• If there is no WHERE clause, all rows will be deleted.
• If a WHERE clause is used, only the rows satisfying the condition will be deleted.
• The table itself is not dropped; only the data inside gets deleted.

[ Option B ]

MICR : Magnetic Ink Character Recognition

• Special technology used in banking to process cheques quickly and accurately.
• The numbers at the bottom of cheques are printed using magnetic ink, which can be read by MICR readers even if the cheque is slightly damaged. This ensures fast and error-free processing of financial transactions.

Digitizer : Converts drawings or images into digital form. It is commonly used in graphic design and CAD (Computer-Aided Design) applications.

Barcode Reader (BCR) : Reads barcodes on products. It helps in fast product identification and inventory management in stores and warehouses.

Captcha : Used to verify human users online, not for banking. It prevents automated bots from accessing websites and submitting forms.

[ Option C ]

A Rootkit is a type of Malicious Software (Malware) designed to gain unauthorized administrator-level control over an operating system. Once installed, it alters the normal functioning of the OS, allowing the attacker to take full control of the system and act as its administrator.

Rootkits are especially dangerous because they actively hide themselves, making detection and removal very difficult.

[ Option C ]

An INI file (initialization file (.ini)) in Windows 95 is a plain text configuration file used to store settings and configuration data for the operating system and applications. These files are organized into sections containing key-value pairs and are readable and editable using any text editor like Notepad.

[ Option B ]

A Network Layer firewall functions as a Packet Filter. It examines and manages the flow of data packets according to rules defined by IP addresses, Port Numbers, and communication protocols. Operating at the Network Layer (Layer 3) of the OSI model, this type of firewall makes decisions on whether to permit or deny packets without analyzing the actual data content inside them.

[ Option C ]

[ Option D ]

To run the slide show from the beginning, press the F5 key, which starts the presentation from the very first slide. If we want to run the slide show from the currently selected slide, press Shift + F5, which begins the presentation from that particular slide without going back to the first one.

[ Option D ]

When an IP packet arrives, the first 8 bits of its header play a crucial role in determining how it is processed. These 8 bits are divided into two fields: the first 4 bits represent the IP version, and the next 4 bits indicate the Internet Header Length (IHL).

In this case, the first 8 bits are 01000010. The first 4 bits, 0100, correspond to version 4, which confirms that this is an IPv4 packet. The next 4 bits, 0010, represent the IHL value of 2.

The IHL specifies the number of 32-bit words in the header. Since each word equals 4 bytes, the total header length here is 2 × 4 = 8 bytes. However, the minimum valid IPv4 header length is 20 bytes (IHL = 5).

Therefore, an IHL value of 2 is invalid and indicates a malformed packet. As a result, the receiver will reject this packet because it does not meet the minimum requirements for processing.

[ Option B ]

HTTP (Hypertext Transfer Protocol), is the standard protocol used to transfer web pages over the internet. It works at the Application Layer, allowing communication between web browsers and web servers. When a browser requests a webpage, HTTP facilitates sending that request to the server and receiving the webpage content, such as HTML, images, and videos, in response.

This protocol follows a client-server model, where the browser acts as the client initiating the request, and the server processes the request and sends back the required webpage data. Through this request-response communication, HTTP enables users to access and view websites on the internet efficiently.

[ Option A ]

In Microsoft PowerPoint 2016, the Presentation Views help users create, organize, and customize slides effectively. The main options are:
Normal View: This is the default editing view where you can work on individual slides. It shows the slide pane, outline pane, and notes pane, allowing users to design slides and add content.
Outline View: Displays the text content of all slides in a structured outline format. This view is useful for organizing ideas and editing slide text efficiently.
Slide Sorter View: Shows all slides as thumbnails on a single screen. This view helps in rearranging, deleting, or duplicating slides quickly.
Notes Page View: Displays each slide along with its speaker notes. This view is useful for reviewing and editing notes before presentations or printing.
Reading View: Presents the slides in full-screen mode but within the PowerPoint window. It is useful for reviewing the presentation without switching to Slide Show mode.