C Operators Quiz - MCQ Questions and Answers

1. What is the result of the expression 5 + 3 * 2 in C?

a) 16

b) 11

c) 13

d) 10

Answer:

b) 11

Explanation:

According to operator precedence in C, multiplication is performed before addition. Hence, 3 * 2 is evaluated first, making the expression 5 + 6, which equals 11.

2. What does the '++' operator do in C?

a) Addition

b) Subtraction

c) Increment by 1

d) Increment by 2

Answer:

c) Increment by 1

Explanation:

The '++' operator increments the value of a variable by 1.

3. Which of the following is a logical operator in C?

a) &

b) |

c) !

d) %

Answer:

c) !

Explanation:

The '!' operator is a logical NOT operator in C. The '&' and '|' are bitwise operators, and '%' is the modulo operator.

4. What is the purpose of the bitwise AND operator '&' in C?

a) To compare two values

b) To add two values

c) To perform a logical AND operation

d) To perform a bitwise AND operation

Answer:

d) To perform a bitwise AND operation

Explanation:

The '&' operator performs a bitwise AND operation, comparing each bit of its first operand to the corresponding bit of its second operand.

5. Which operator is used for division in C?

a) /

b) DIV

c) %

d) *

Answer:

a) /

Explanation:

The '/' operator is used for division in C.

6. What does the '==' operator do in C?

a) Assigns a value to a variable

b) Compares two values for equality

c) Adds two values

d) Subtracts one value from another

Answer:

b) Compares two values for equality

Explanation:

The '==' operator is used to compare two values to determine if they are equal.

7. What is the result of the expression 8 % 3 in C?

a) 2.67

b) 2

c) 5

d) 3

Answer:

b) 2

Explanation:

The '%' operator returns the remainder of the division of 8 by 3, which is 2.

8. What is the output of the following C code?

   int a = 5, b = 10;
   printf("%d", a > b && a != b);

a) 0

b) 1

c) 5

d) 10

Answer:

a) 0

Explanation:

The expression evaluates to false (0) because a is not greater than b, even though a is not equal to b.

9. Which operator is used to check if two variables are not equal in C?

a) =

b) !=

c) ===

d) =!

Answer:

b) !=

Explanation:

The '!=' operator checks if two variables are not equal.

10. What is the purpose of the conditional (ternary) operator '?:' in C?

a) To execute a function based on a condition

b) To assign a value based on a condition

c) To compare three values

d) To concatenate strings

Answer:

b) To assign a value based on a condition

Explanation:

The ternary operator '?:' is used to assign a value to a variable based on a condition. It's a shorthand for the if-else statement.

11. How does the bitwise OR operator '|' work in C?

a) It sets a bit if it is set in either operand

b) It sets a bit if it is set in both operands

c) It inverts each bit of its operand

d) It shifts the bits of the first operand

Answer:

a) It sets a bit if it is set in either operand

Explanation:

The '|' operator performs a bitwise OR operation, where a bit is set to 1 if it is set in either operand.

12. What is the result of the expression 5 << 2 in C?

a) 10

b) 20

c) 25

d) 7

Answer:

b) 20

Explanation:

The '<<' operator is the left shift operator. It shifts the bits of 5 (which is 0101 in binary) 2 places to the left, resulting in 10100, which is 20 in decimal.

13. What is the precedence of the '+' and '*' operators in C?

a) '+' has higher precedence than '*'

b) '*' has higher precedence than '+'

c) Both have the same precedence

d) Depends on the compiler

Answer:

b) '*' has higher precedence than '+'

Explanation:

In C, the '*' (multiplication) operator has higher precedence than the '+' (addition) operator.

14. What does the 'sizeof' operator return in C?

a) The size of a variable in bits

b) The size of a variable in bytes

c) The length of an array

d) The number of elements in an array

Answer:

b) The size of a variable in bytes

Explanation:

The 'sizeof' operator returns the size of a variable or data type in bytes.

15. What is the output of the following C code?

  int x = 9, y = 4;
   printf("%d", x & y);

a) 0

b) 1

c) 5

d) 13

Answer:

c) 5

Explanation:

The '&' operator performs a bitwise AND operation. In binary, 9 is 1001 and 4 is 0100. The AND operation of these gives 0001, which is 5 in decimal.

16. What is the result of the expression 5 | 3 in C?

a) 8

b) 7

c) 6

d) 5

Answer:

b) 7

Explanation:

The '|' operator performs a bitwise OR operation. In binary, 5 is 0101 and 3 is 0011. The OR operation of these gives 0111, which is 7 in decimal.

17. What is the output of the following C code?

int a = 10;
   printf("%d", !a);

a) 0

b) 1

c) 10

d) -10

Answer:

a) 0

Explanation:

The '!' operator is the logical NOT operator. It inverts the truthiness of a, and since a is non-zero, !a is 0.

18. What does the '->' operator do in C?

a) Accesses a member of a structure through a pointer

b) Accesses a member of an array

c) Performs a bitwise operation

d) Compares two pointers

Answer:

a) Accesses a member of a structure through a pointer

Explanation:

The '->' operator is used to access a member of a structure or a union through a pointer.

19. What is the result of the expression '5 == 5' in C?

a) True

b) False

c) 5

d) Error

Answer:

a) True

Explanation:

The '==' operator compares two values for equality. Since 5 is equal to 5, the expression evaluates to true (1).

20. What is the output of the following C code?

int a = 5;
   int b = a++;
   printf("%d %d", a, b);

a) 5 6

b) 6 5

c) 6 6

d) 5 5

Answer:

b) 6 5

Explanation:

The post-increment operator 'a++' increments 'a' after its current value is assigned to 'b'. So, 'b' becomes 5, and 'a' becomes 6.