Multiple Choice Questions (MCQs)

In this guide, you'll find a collection of essential C language MCQs, These cover important questions asked in previous held exams and important questions from exam point of view.

Question 1:

Compiler generates..........files.

• A) Executable code
• B) Object code
• C) Assembly code
• D) None of these

Answer:

• B) Object code

Question 2:

What function can be used to free the memory allocated by calloc?

• A) Dealloc
• B) Streat
• C) Free
• D) Memory

Answer:

• C) Free

Question 3:

What will be the output of the following C code?

#include <stdio.h>
void main() {
    char a = 'a';
    int x = (a % 10)++;
    printf("%d\n", x);
}

• A) 6
• B) Junk value
• C) Compile time error
• D) 7

Answer:

• C) Compile time error

Question 4:

What is the maximum number of dimensions an array in C may have?

• A) Two
• B) Eight
• C) Twenty
• D) Theoretically no limit

Answer:

• D) Theoretically no limit

Question 5:

Which of the following is a correct syntax to declare a pointer in C?

• A) int *ptr;
• B) int ptr*;
• C) int ptr;
• D) pointer int ptr;

Answer:

• A) int *ptr;

Question 6:

What is the size of int in C?

• A) 2 bytes
• B) 4 bytes
• C) 8 bytes
• D) 16 bytes

Answer:

• B) 4 bytes

Question 7:

Which of the following is used to terminate a string in C?

• A) \0
• B) \n
• C) \t
• D) \r

Answer:

• A) \0

Question 8:

What does the sizeof() operator return in C?

• A) The number of elements in an array
• B) The total memory used by a variable in bytes
• C) The address of a variable
• D) The data type of a variable

Answer:

• B) The total memory used by a variable in bytes

Question 9:

Which of the following is NOT a valid pointer operation in C?

• A) ptr++
• B) ++ptr
• C) ptr+2
• D) ptr--2

Answer:

• D) ptr--2

Question 10:

Which header file is required for the printf() function in C?

• A) #include <stdlib.h>
• B) #include <stdio.h>
• C) #include <conio.h>
• D) #include <math.h>

Answer:

• B) #include <stdio.h>

Question 11:

Which of the following is used for a comment in C?

• A) // comment
• B) /* comment */
• C) <!-- comment -->
• D) Both A and B

Answer:

• D) Both A and B

Question 12:

What is the output of the following code?

#include <stdio.h>
int main() {
    int a = 5, b = 2;
    printf("%d", a / b);
    return 0;
}

• A) 2.5
• B) 2
• C) 0
• D) 5

Answer:

• B) 2

Question 13:

Which of the following is true about a for loop in C?

• A) Initialization is executed only once
• B) The condition is checked before each iteration
• C) Increment/decrement is executed after each iteration
• D) All of the above

Answer:

• D) All of the above

Question 14:

What is the purpose of the break statement in C?

• A) To terminate the loop entirely
• B) To skip the current iteration of the loop
• C) To jump to the next case in a switch statement
• D) None of the above

Answer:

• A) To terminate the loop entirely

Question 15:

Which operator is used to access members of a structure through a pointer in C?

• A) .
• B) ->
• C) &
• D) *

Answer:

• B) ->

Question 16:

Which of the following is not a reserved keyword in C?

• A) auto
• B) case
• C) main
• D) default

Answer:

• C) main

Question 17:

A C variable cannot start with:

• A) A number
• B) An alphabet
• C) Both of these
• D) A special symbol other than underscore

Answer:

• A) A number

Question 18:

What does the following declaration mean?

int (*ptr)[10];

• A) ptr is an array of pointers to 10 integers
• B) ptr is a pointer to an array of 10 integers
• C) ptr is an array of 10 integers
• D) ptr is a pointer to an integer

Answer:

• B) ptr is a pointer to an array of 10 integers

Question 19:

The keyword used to transfer control from a function back to the calling function is:

• A) switch
• B) goto
• C) go back
• D) return

Answer:

• D) return

Question 20:

Specify the two library functions to dynamically allocate memory:

• A) malloc() and memalloc()
• B) alloc() and memalloc()
• C) malloc() and calloc()
• D) memalloc() and foralloc()

Answer:

• C) malloc() and calloc()