Informatics Assistant (IA) 2023 Paper Solution

[ Option C ]

The given algorithm calculates the factorial of a number N using a function that calls itself with N−1, a clear example of Recursion.

[ Option D ]

When we access a website, we use a web address (URL) that contains several parts, each serving a specific function, from identifying the protocol used to specifying the exact web page we want to view.

In the web address (URL), http://www.ncert.nic.in/textbook/textbook.htm

[ Option C ]

Dot Matrix Printers are Impact Printers that use tiny pins to strike an ink ribbon, forming characters or images as a pattern of dots on paper.
They are called Serial Printers because they print one character at a time, moving horizontally across the page.
In contrast, line printers print one entire line at a time, and page printers (laser printers) print a full page at once.

[ Option B ]

[ DELETE ]

The question uses the term “software,” but the given options:

• HTML : It is markup language and used for creating static web pages only, not dynamic.
• Google : It is a search engine, not a web development tool.
• Filmora : It is a video editing software, not for web pages.
• Ruby : Ruby itself is not a software application, but a programming language. However, it is often associated with the Ruby on Rails framework, which is software used for building dynamic and database-driven websites efficiently.

[ Option B ]

In MS Word, the Insert Tab is used to add various elements into a document, such as tables, pictures, charts, shapes, headers, footers, and page numbers.

[ Option C ]

[ Option C ]

An IDE (Integrated Development Environment) provides all the necessary development tools such as text editors, compilers, debuggers, code libraries, and testing platforms within a Single integrated framework.

[ Option C ]

Inheritance is a fundamental concept in object-oriented programming (OOP) where one class acquires the properties (data fields) and methods of another class. The class inheriting the properties is called the derived class or subclass or child class, while the class from which it inherits is called the base class or superclass or parent class. Inheritance promotes code reusability.

[ Option B ]

An Integrated Development Environment (IDE) suite consolidates the basic tools required to write, test, and debug software. IDEs provide a comprehensive environment combining code editors, compilers or interpreters, debuggers, and testing tools, all accessible from one interface.

[ Option B ]

A pen drive, also called a USB (Universal Serial Bus) flash drive, is designed to be inserted into a USB port on computers, laptops, and many other devices.
The USB port allows easy plug-and-play functionality for transferring or storing data, making it the most common interface for pen drives.

[ Option A ]

A QR Code (Quick Response Code) has three position-detection squares that help scanners identify the orientation of the code.

• Two squares are located at the top-left and top-right corners.
• The third square is located at the bottom-left corner.

These position markers allow QR readers to quickly detect, align, and decode the information, regardless of the code’s angle or rotation.

[ Option C ]

An IDE (Integrated Development Environment) provides a single platform where developers can write, compile, debug, and manage code. Without an IDE, a developer must handle each tool Separately:

• Write code in a text editor.
• Compile using a compiler.
• Debug using a separate debugger.
• Manage libraries and dependencies manually.

[ Option B ]

Data Abstraction is the separation of the logical view of data from its implementation details. It allows users to interact with data at a high level without needing to understand the complex underlying details of how data is stored or manipulated. For example, in a database, users can query employee names and salaries without knowing the underlying storage structure or file formats.

[ Option A ]

WannaCry was a ransomware attack that occurred in May 2017, infecting over 2,00,000 computers across 150 countries. It encrypted users’ data and demanded payment in Bitcoin cryptocurrency to restore access, hence the name “WannaCry” because victims were left helpless.

• It exploited a vulnerability in Microsoft Windows (SMB protocol).
• The attack affected major organizations like UK’s National Health Service (NHS), FedEx, and Renault.

[ Option D ]

In flowchart representations of algorithms, the Parallelogram is used to represent Input-Output operations.

[ Option A ]

The repeated division method by 2 is used to convert a decimal (base 10) number into a binary (base 2) number.
Steps:
1. Divide the decimal number by 2.
2. Record the remainder.
3. Use the quotient for the next division by 2.
4. Repeat until the quotient becomes 0.
5. The binary number is formed by reading the remainders from bottom to top.

[ Option B ]

The File System in an Operating System (OS) provides a way to store, organize, and manage files on storage devices. It allows the system to:

• Create and delete files.
• Organize files into directories and folders.
• Control access and provide protection from unauthorized users.
• Maintain metadata like file size, type, timestamps and permissions.

[ Option C ]

When a computer is powered on, the BIOS (Basic Input/Output System) is responsible for initializing hardware, performing system checks, and loading the operating system into main memory so that the computer can start functioning.

[ Option A ]

WWW (World Wide Web) is not a search engine, it is a system of interlinked hypertext documents (collection of websites) accessible via the Internet. It is the platform on which websites and search engines operate.

A Search Engine is a software system that helps users find information on the Internet. It works by crawling web pages, indexing their content, and then retrieving the most relevant results when a user enters a query.

Search engines use algorithms to rank web pages based on factors like keywords, content quality, backlinks, and user engagement. The list of some important search engine are:

[ Option A ]

OPENING POP-UPS is not a way to protect your system, in fact, it is one of the most common ways malware spreads. Pop-ups may contain malicious links, fake ads, or phishing content that can install harmful software on your device.

To stay protected from malware, never click on suspicious pop-ups, use firewalls and antivirus software, and regularly back up important data.

[ Option A ]

The On-Screen Keyboard is a Virtual Keyboard provided by an operating system that displays QWERTY keys on the screen that allows users to input text by clicking keys using a mouse or touch input instead of a physical keyboard.

Although keyloggers can exploit it by recording screen activities, it is still safer than hardware keyboards, which can be compromised by physical keyloggers.

[ Option C ]

A Plug-In is a complete software component developed by a third party that is installed on a host application, such as a web browser, to extend its capabilities. 
Plug-Ins allow browsers to perform additional functions like playing videos, displaying PDFs, or running multimedia content. Examples include Adobe Flash Player, Java Plug-in, PDF Viewer etc.

Plug-Ins differ from Add-Ons or Extensions, which are usually smaller tools that modify or enhance the browser’s behavior, while plug-ins provide additional functionality through external software integration.
 

[ Option C ]

Virtual Memory is a technique where part of secondary storage (HDD/SSD) is used by the computer as if it were an extension of the main memory (RAM).

• Run larger programs than the available physical RAM.
• Increase multitasking efficiency by swapping data between RAM and disk storage.

The Operating System (OS) manages this process using paging or segmentation, ensuring smooth performance even when physical memory is limited.

[ Option A ]

A Binary File stores data in machine-readable format using binary digits (bits), which are 0s and 1s. These digits represent the on and off states in digital circuits, making it a format that computers can directly read and process.

Unlike Text Files which store alphabets, numbers, and special characters in readable format, binary files store data in a very compact and efficient way using only 0s and 1s.

[ Option C ]

• In row 1, A1 is 60 and C1 is 75, so 60 ≠ 75 : Output is F.
• In row 2, A2 is 70 and C2 is 70, so 70 = 70 : Output is T.
• In row 3, B3 is 90 and D3 is 90, so 90 = 90 : Output is T.
   

[ Option C ]

An Array is a Homogeneous Data Structure, meaning it stores elements of the same data type. In most programming languages like C, C++, and Java, array indexing starts from 0.

[ Option D ]

System on a Chip (SoC) is a highly integrated microchip that contains all the essential components of a computer or smartphone including processor cores (CPU), memory (RAM and ROM), Graphics Processing Unit (GPU), input/output controllers, modems, and other peripherals on a single chip.

SoCs are designed to fit into compact devices like smartphones, enabling them to run efficiently with reduced space, power consumption, and heat dissipation.

Unlike a processor on a chip, which only contains the CPU, an SoC includes multiple functional units to handle computing, graphics, and communication.
 

[ Option A ]

Ethernet networks use MAC (Media Access Control) addresses as their physical addresses, which are permanently imprinted on the Network Interface Card (NIC) by the manufacturer. A MAC address is 48 bits long, equivalent to 6 bytes, and is usually represented in hexadecimal notation.
This unique identifier ensures that devices within the same local network can correctly recognize and communicate with each other.

[ Option A ]

To display a list of online sites that students can use as resources, the best feature in a Word document is Linking (hyperlinks). This feature allows embedding clickable links to websites directly in the document, enabling easy access to online resources.

[ Option C ]

A Firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules. Its primary purpose is to protect a trusted internal (LAN) network from untrusted external networks like the Internet.

Firewalls can be hardware, software, or a combination of both, and act as a barrier or gatekeeper between networks by allowing or blocking data packets depending on security policies.

[ Option B ]

The OSI (Open Systems Interconnection) model is a conceptual framework used to understand and standardize how different networking systems communicate over a network. It divides network communication into 7 layers, each serving a specific function.

[ Option D ]

In a Bus Topology, all computers are connected to a single central cable called the bus or backbone. Data sent by one computer is received by all others on the same network segment. This design makes it simple and inexpensive, but also less secure and less reliable compared to other topologies.

Network Topology refers to the physical or logical arrangement of computers, cables, and other devices in a network. It defines how nodes (computers, printers, switches, etc.) are connected and how data flows between them. There are two main types:

• Physical Topology: The actual layout of cables, wires, and devices.
• Logical Topology: How data flows across the network, regardless of physical connections.

Choosing the right topology affects network performance, scalability, cost, and reliability.

[ Option D ]

IDEs is a software application that provides comprehensive facilities to computer programmers for software development, combining essential tools like code editors, compilers, debuggers, and build automation into a single interface.

[ Option C ]

LCD (Liquid Crystal Display) panels work on the principle of light modulation. The main job of an LCD is to "modulate" light, not generate it.

Instead of producing light by themselves, LCDs use a backlight behind the panel. The liquid crystals in the display control how much light passes through to create the images you see. To do this, the crystals change their orientation when electricity is applied, allowing more or less light to pass through each part of the display.

Common Display Technologies:

[ Option C ]

The child's action of looking right and left before crossing the road represents a decision-making process. In algorithms, Selection refers to a choice or decision based on a condition.

[ Option C ]

The Right Button is used to open a context menu (shortcut menu) that displays a list of commands or options relevant to the selected item or area on the screen.
The Left Button is mainly used for selection and clicking, while the Centre Button (Scroll Wheel) is used for scrolling.

[ Option A ]

Web-based IDEs are online development environments that allow developers to write, run, and debug code through a web browser without installing heavy software locally.

Microsoft Visual Studio Code (VS Code) is a popular IDE that supports web development, including HTML, CSS, JavaScript, and backend languages. It also has extensions for collaborative web-based development.

[ Option C ]

To find the binary number that, when divided by 11 (binary), gives a quotient of 10 (binary), we first convert the binary numbers to decimal for easier calculation. The divisor 11 in binary is equal to 3 in decimal, and the quotient 10 in binary is equal to 2 in decimal.

Using the formula for division, Dividend = Divisor × Quotient + Remainder, and assuming the remainder is zero, we calculate the dividend as 3 × 2 = 6. Converting 6 back into binary gives 110.

Therefore, dividing the binary number 110 by 11 results in a quotient of 10, making 110 the correct binary number for this question.

[ Option C ]

A Switch is an intelligent networking device used to connect multiple computers or devices within a Local Area Network (LAN).

The switch operates at the Data Link Layer (Layer 2) of the OSI Model and is capable of reading the MAC (Media Access Control) address from each incoming data packet. The switch then forwards the packet only to the specific device (destination) for which it is intended.

This selective forwarding reduces network traffic and collisions, improving overall network efficiency and security.

[ Option D ]

[ Option C ]

A Pen Drive (USB Flash Drive) is a Solid-State storage device that uses flash memory to store data. It connects to a computer via a USB Port and is commonly used for data transfer, storage, and backup.

[ Option B ]

A Register is a small and very fast storage location inside the CPU (Central Processing Unit) used to temporarily hold data, instructions, or addresses that the CPU needs immediately during processing.

[ Option B ]

[ Option D ]

In C programming, the break statement is used to immediately exit a loop (for, while, or do-while), skipping the remaining statements in the loop body. When the break statement is encountered, control transfers to the statement immediately following the loop body.

• The continue statement instead skips the rest of the current iteration but continues with the next iteration of the loop.

for(int i = 1; i <= 8; i++) {
    if(i == 4) {
        break; // exits the loop when i equals 4
    }
    printf("%d ", i);
}
Output: 1 2 3

[ Option B ]

Binary Search is an efficient search algorithm that works on the principle of divide and conquer:

• It assumes the array is Sorted in ascending or descending order.
• It compares the target value with the middle element of the array.
  • If equal then item is found.
  • If smaller then search the left half.
  • If larger then search the right half.

With each comparison, half of the array is eliminated, making the search faster than Linear Search.

[ Option A ]

[ Option D ]

To convert a binary number to hexadecimal, group the binary digits in sets of 4 (adding leading zeros if necessary), then convert each group to its hexadecimal equivalent and combine.

Step 1:
Group the binary number into 4-bit groups from right to left:
111111000101101001
Since the leftmost group has only 2 bits, we can pad with 2 leading zeros:
0011 1111 0001 0110 1001
Step 2:
Convert each 4-bit group to hexadecimal:

• 0011 : 3
• 1111 : F
• 0001 : 1
• 0110 : 6
• 1001 : 9

Combine the hexadecimal digits:
(111111000101101001)₂ = (3F169)₁₆
 

[ Option B ]

To check if the values of three variables age1, age2, and age3 are equal in C programming (and most languages), you use the equality operator == (Equal to) along with logical AND (&&) to combine multiple conditions.
Remember, the operator = is called assignment operator which is used for assign the value to the left-hand side operand (variable).

[ Option B ]

A Repeater is a networking device used to amplify and regenerate weak signals to extend the transmission distance between network devices. Repeaters operate at the Physical Layer (Layer 1) of the OSI model and do not route or manage traffic. They simply regenerate signals to maintain quality over longer distances.

Modem: A device that converts digital signals from a computer into analog signals for transmission over telephone lines or cable networks, and vice versa. It enables devices to connect to the Internet.

Router: A networking device that directs data packets between different networks, such as between a LAN and the Internet, ensuring that data reaches the correct destination efficiently.

[ Option C ]

All search engines use Metadata, which is data about data. Metadata provides information describing other data, for example, a file’s name, size, date created, author, or content type.

In the context of Search Engines, metadata helps in organizing, indexing, and retrieving web pages efficiently. For instance, HTML meta tags (title, description, keywords) tell search engines what a webpage is about, improving its visibility in search results.

[ Option B ]

IDE stands for Integrated Development Environment. It is a software application that provides comprehensive facilities to computer programmers for software development, combining essential tools like code editors, compilers, debuggers, and build automation into a single interface.
Common examples of IDEs are Visual Studio Code, Eclipse, PyCharm, NetBeans etc.

[ Option D ]

Microsoft PowerPoint allows you to export a presentation as an MP4 video file. This feature is useful for sharing or uploading presentations as videos without requiring PowerPoint software to view them.

To create an MP4, you go to File > Export > Create a Video, select the quality and settings, and save the presentation as an MP4 file.

[ Option B ]

Copyright is a form of Intellectual Property Right (IPR) that grants legal protection to creators for their original works such as books, music, software, art, and digital content.

• It ensures that only the creator (or the person authorized by them) has the exclusive right to reproduce, distribute, or modify their work.
• Copyright helps prevent unauthorized copying, sharing, or misuse of digital content in today’s data-driven world.

[ Option C ]

An optical mouse uses a Light-Emitting Diode (LED) as its light source.

• The LED shines light onto the surface below the mouse.
• A sensor captures the reflected light and detects movement by analyzing changes in the pattern of reflected light.
   

[ Option B ]

Each digit after the binary point represents a negative power of 2. By summing these values, we convert the binary fraction to its decimal equivalent. To convert a binary fraction to decimal, use the formula:

0.b1b2b3b4 = b1×2⁻¹ + b2×2⁻² + b3×2⁻³ + b4×2⁻⁴

Given: 
(0.1011)2 =1×2⁻¹ + 0×2⁻² + 1×2⁻³ + 1×2⁻⁴
=0.5+0+0.125+0.0625
=0.6875
So, (0.1011)₂ = (0.6875)₁₀
 

[ Option A ]

In a Mesh Topology, every computer (node) is connected directly to every other computer in the network. If there are n computers, each computer connects to (n − 1) others.
Number of connections (links / wires) = (n*(n-1))/2. If there are 5 computers, then (5*(5-4)/2) = 5*4/2 =10. So, 10 cables are required to form a full mesh.

• Note, Mesh Topology offers high reliability and fault tolerance, but requires many cables as the network grows.

[ Option A ]

Round Robin (RR) is a preemptive CPU scheduling algorithm used in operating systems.

• In RR, each process is assigned a fixed time slice (quantum) for execution.
• If a process does not finish in its time quantum, it is preempted and moved to the end of the ready queue, allowing the next process to execute.
• This ensures fair CPU allocation among all processes and is commonly used in time-sharing systems.

CPU Scheduling is the method by which an operating system decides which process in the ready queue will get the CPU next. The main goal is to maximize CPU utilization, minimize waiting time, and ensure fair access to processes. The CPU scheduling mainly two types:

1. Preemptive Scheduling : The CPU can be taken away from a running process if a higher-priority process arrives or its time quantum expires.
   • Examples:
   • Round Robin (RR).
   • Shortest Remaining Time First (SRTF).
   • Priority Scheduling (Preemptive).
2. Non-Preemptive Scheduling : Once a process starts execution, it cannot be interrupted until it finishes or voluntarily yields the CPU.
   • Examples:
   • First-Come, First-Served (FCFS).
   • Shortest Job Next (SJN) / Shortest Job First (SJF).
   • Priority Scheduling (Non-Preemptive).

[ Option B ]

Digital Signals are discrete signals that represent information using distinct values, often in binary form (0s and 1s). They are generated by digital modulation techniques and are used in computers, digital communication, and networking devices.

Unlike Analog Signals, which are continuous, digital signals are less prone to noise and distortion, making them more reliable for data transmission.

[ Option C ]

NetBeans IDE (Integrated Development Environment) provides a visual design interface for building the front end of applications. This allows developers to drag and drop UI components onto a form without writing all the code manually.

Radio Button is an example of a front-end component that can be added using this drag-and-drop feature in NetBeans. Other examples include buttons, text fields, checkboxes, labels, and panels.

[ Option C ]

Relational operators perform comparisons like equal to, not equal to, less than, greater than, etc. The Arithmetic Logic Unit (ALU) evaluates these comparisons and outputs one of two possible values, typically, 0 (false) or 1 (true).

Thus, the maximum number of outputs the ALU can give for relational operations is 2, representing true or false conditions.

[ Option A ]

When a program written in a high-level language is processed by a computer, it goes through a systematic sequence of operations:

[ Option D ]

MICR stands for Magnetic Ink Character Recognition. It is a technology used by banks to print a special code at the bottom of cheques. This code uses a unique ink with magnetic particles, which makes it possible for machines to read and verify the printed numbers quickly and securely.
Mahi cannot change or alter this code because magnetic ink and special fonts are used, which prevent tampering or duplication.

[ Option B ]

FIFO (First In First Out) is a scheduling or data handling method where the first process or item that enters the queue is the first one to be processed or removed. It works much like a queue where the earliest request is served before others.

[ Option B ]

WYSIWYG stands for "What You See is What You Get." The term WYSIWYG is used in computing, especially in word processors, desktop publishing, and page layout software.

[ Option A ]

For simple internet connectivity at home, the gateway that allows users to connect to the Internet is typically provided by the Internet Service Provider (ISP).

When you access the internet from your home (through Wi-Fi, broadband, or mobile data), your ISP provides the necessary network connection, IP address, and routing to link your local network to the global Internet. Some examples of ISP are BSNL,VI,  Airtel, Jio, ACT, Hathway, etc.

[ Option B ]

In C programming, Preprocessor Directives are lines included in the code that are processed before compilation. These directives always begin with the # (Hash) symbol. Examples of commonly used preprocessor directives starting with # include, #define, #ifdef, #ifndef etc.

[ Option A ]

Access is a database software used to store, organize, and manage related data efficiently. Query is a powerful feature in Access that allows users to filter, search, and extract specific information based on certain conditions.

[ Option D ]

A Printer is an output device that produces a hard copy of text, images, or graphics from a computer or other digital devices.
An Impact Printer is a type of printer that creates images on paper by physically striking an ink ribbon against the paper, similar to how a typewriter works.
Dot Matrix Printers use several tiny pins in a print head. When these pins hit the inked ribbon, they form letters, numbers, or graphics as patterns of dots. This technology is called "Dot Matrix" because the printed results are actually made up of small dots, arranged in a grid (matrix).

Other types of printers:

[ Option D ]

In a Local Area Network (LAN), devices can be connected either wirelessly using Wi-Fi or wired using Ethernet Cables. Ethernet cables provide a reliable, high-speed, and stable connection between computers, printers, switches, and other network devices within the LAN.

[ Option B ]

Voice over Internet Protocol (VoIP) technology converts analog voice signals into digital data and then transmits them over broadband internet lines. This digital conversion allows voice communication to be sent as packets over IP networks rather than traditional telephone lines.

• VoIP uses an Analog-to-Digital Converter (ADC) to sample and digitize the analog voice signals.
• These digital signals are then compressed, packetized, and sent over the internet.
• On the receiving end, the digital signals are converted back to analog for playback.
• Examples include Skype, Zoom voice calls, Google Meet audio, and other internet calling services.

[ DELETE ]

[ DELETE ]

[ Option A ]

Logical operators are used in programming and algorithms to perform decision-making based on true or false of conditions.

[ Option B ]

All information transmitted over the Internet uses the Packet Switching method. In packet switching, data is broken into small packets before being sent across the network.

• Each packet contains the source address, destination address, and sequence information, allowing it to find the best route to the destination independently.
• At the destination, packets are reassembled to form the original data.

Switching Techniques are methods used in network communication to transfer data from a source device to a destination device across a network. They determine how data travels, whether through a dedicated path, divided into packets, or stored temporarily before forwarding.

[ Option A ]

Analog Signals represent continuous data and real-world phenomena such as smell, speech, temperature, or pressure that vary smoothly.
Digital Signals are discrete and represent data in binary form, such as scanning, which converts images or documents into digital data.

[ Option C ]

IPSEC, IP encapsulation, and tunneling are technologies used primarily in Virtual Private Network (VPN) to securely transmit data over public or untrusted networks like the Internet.

• IPSEC (Internet Protocol Security) provides encryption and authentication at the IP layer.
• IP Encapsulation wraps data packets so they can travel securely through the VPN tunnel.
• Tunneling enables data to be sent from one network to another safely even over an insecure network.

[ Option C ]

Remote Login allows a user to access and control a computer from a different location over a network, typically the Internet. Telnet (Terminal Network) is a protocol used for remote login, allowing users to log in to a remote computer and execute commands as if they were physically present. Telnet uses Port 23.

[ Option B ]

A Cookie is a small text file stored on a user’s computer by a web browser when visiting a website.
Cookies store information about the user's interactions and preferences on the site to provide a better personalized experience. They help websites remember login status, items in shopping carts, user settings, and track user activity for analytics or advertising.

Session Cookies are temporary cookies that are created when a user starts an online session and are automatically deleted when the browser is closed or the session expires.

[ Option B ]

The Kernel is the core part of an operating system that permanently resides in main memory (RAM).

• It manages system resources, CPU scheduling, memory management, I/O operations, and communication between hardware and software.
• All other parts of the OS rely on the kernel to perform basic functions and ensure smooth operation of the system.

[ Option A ]

File modes control the type of access you have to a file. When a file is opened in the mode <r>, it means the file is opened for reading only. In this mode, you can only view or read the contents of the file, but you cannot make any changes like writing, deleting, or overwriting the file.

[ Option A ]

In network security, communication between two devices can be intercepted by malicious users. Eavesdropping is the unauthorized real-time interception or monitoring of private communication between two entities over a network. It can involve listening to voice calls, reading emails or data transmissions without consent, exploiting unsecured or weakly secured communication channels.
Phishing : Fraudulent attempt to obtain or steal sensitive information like passwords.
Virus : Malicious Software (Malware) designed to damage or disrupt systems.

[ Option B ]

The rightmost bit of a binary number is known as the Least Significant Bit (LSB). It represents the smallest value in binary positional notation, corresponding to 2⁰=1.

The opposite is the Most Significant Bit (MSB), which is the leftmost bit and represents the largest value place in the binary number, corresponding to 2^n-1.

[ DELETE ]

In C Language, user-defined functions are not written using any specific keyword, instead, user-defined functions are simply declared and defined using the typical function syntax.
Return_Type function_name(Parameter_List)
{
    // function body.
}

[ Option A ]

A touchpad (trackpad) on laptops and other devices is a sensitive flat surface that detects the movement and position of your fingers to control the mouse cursor on the screen.

• A Stylus is used mainly with touchscreens or graphic tablets, not with touchpads.

[ Option B ]

The octal number system is a base-8 number system, which means it uses 8 digits: 0, 1, 2, 3, 4, 5, 6, and 7. Each place value in octal represents a power of 8.

[ Option C ]

In Java programming, the Java source code (.java) is first compiled by the Java Compiler into Byte Code (.class). Byte Code is a standardized machine-independent code that can be executed on any platform using the Java Virtual Machine (JVM).

[ Option B ]

A Modem (Modulator-Demodulator) is a device that allows computers to communicate over telephone lines or other analog transmission media.

• The data originates as digital (0s and 1s) form from the computer.
• The modem converts this digital data into analog signals suitable for transmission over traditional telephone lines or other analog communication media.
• At the receiving end, the modem converts the analog signals back into digital data for the receiver.

This process is called Modulation (Digital to Analog) and Demodulation (Analog to Digital), which is why the device is called a MODEM (Modulator-Demodulator).

[ Option C ]