Learn C MCQs

Prepare C MCQs (Multiple choice Questions) for exam and job interviews.

What is the default return type of a function in C if no return type is specified?

1) int

2) void

3) float

4) char

Answer : int

Which of the following is a valid way to declare a string in C?

1) char str[100];

2) char str[];

3) char *str;

4) All of the above

Answer : All of the above

What does the `strlen()` function do?

1) Calculates the length of a string

2) Concatenates two strings

3) Copies one string to another

4) Converts string to integer

Answer : Calculates the length of a string

What will be the output of printf("%d", 10 / 3);?

1) 3

2) 4

3) 2

4) 3.33

Answer : 3

Which of the following is not a valid C data type?

1) int

2) float

3) char

4) string

Answer : string

What is the output of printf("%d", 4 + 5 * 2);?

1) 14

2) 13

3) 9

4) 10

Answer : 14

Which of the following is used for dynamic memory allocation in C?

1) malloc()

2) calloc()

3) free()

4) All of the above

Answer : All of the above

What will be the output of printf("%d", 5 << 1);?

1) 10

2) 5

3) 15

4) 20

Answer : 10

What is the correct way to declare a function in C?

1) int func()

2) func() int

3) void func()

4) Both 1 and 3

Answer : Both 1 and 3

Which of the following operators is used to access members of a union?

1) .

2) ->

3) ::

4) Both 1 and 2

Answer : Both 1 and 2