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[ Option B ]

In this code, the expression (x | y) performs a bitwise OR on 10 and 5.
10 in binary : 1010
5 in binary :   0101
Bitwise OR : 1111 which is 15.
Next, (a + b) adds the Boolean values:
true : 1
false : 0
So, a + b = 1.
Finally, p = 15 + 1 = 16.

[ Option A ]

In C++, the symbol << is used in two ways: it works as an output operator (also called the insertion or put-to operator) when used with cout, and as a bitwise left shift operator when it appears between two numeric values.

A bitwise left shift moves the bits of a number to the left by a certain number of positions. In the statement cout << "FIRST" << (a << 2) << "SECOND";, the part (a << 2) is calculated like this, since a = 5, its binary form is 0000 0101. When we shift the bits two places to the left, it becomes 0001 0100, which equals 20 in decimal. So, (a << 2) gives the value 20.

Finally, when substituted into the output statement, it becomes cout << "FIRST" << 20 << "SECOND";, which displays the text FIRST20SECOND on the screen. Note that there are no spaces unless explicitly added.

[ Option B ]

In this code, the left shift operator << is applied to the integer a, which has the value 5. The expression a << 2 shifts the bits of 5 two positions to the left. In binary, 5 is 00000101, and shifting it left by 2 positions gives 00010100, which is 20 in decimal.
Then, the cout statement prints "FIRST", followed by the result of a<<2, and then "SECOND". As a result, the output of the program is FIRST20SECOND.

[ Option B ]

The comma operator allows multiple expressions to be written in a single statement. Expressions are evaluated from left to right and the result of the last expression is considered, but all expressions are executed.
The statement cout<<"Hello", prints Hello and cout<<a; prints the value of a, which is 23.
Even though there is no semicolon after cout<<"Hello", it does not cause an error because both statements are combined into one statement using the comma operator.

[ Option A ]

In C++, variables declared in inner scopes (blocks, functions) hide outer scope variables with the same name. The scope resolution operator :: accesses the global variable from any nested scope. In statement printf(“%d,%d”,i,::i);

• The i refers to the innermost variable, which is 30.
• The ::i uses the scope resolution operator, which accesses the global variable, which is 10.

[ Option B ]

The operator sizeof is used to find the size (in bytes) of a data type or an expression.
In C++, a character literal like 'a' is treated as a char type. Since the size of char in C++ is always 1 byte, the expression sizeof('a') returns 1.
Note:
In C, a character literal such as 'a' is treated as an int type, not as a char. Therefore, when the sizeof operator is applied to 'a' in C, it returns the size of an int, which is usually 2 bytes (16-bit compiler) or 4 bytes (32-bit compiler).

[ Option C ]

In C++, a numeric value written with a decimal point is treated as a floating-point constant. By default, a floating-point literal without any suffix (f or l) is of type double. The size of a double data type is 8 bytes.

[ Option A ]

In C++, logical operators are used to combine or negate boolean expressions or conditions to evaluate true or false. The logical operators in C++ are:

• && (Logical AND): Returns true if both operands/conditions are true.
• || (Logical OR): Returns true if at least one operand/condition is true.
• ! (Logical NOT): Negates or invert the boolean value (true becomes false, and false becomes true).