Standard Library Functions MCQs

Question 1

What does the 'strcat' function in C do?

Accepted Answer

Concatenates two strings

Answer

Compares two strings

Answer

Copies one string to another

Answer

Searches for a substring

Question 2

Which standard library function is used to find the largest integer less than or equal to a given floating-point number in C?

Accepted Answer

floor()

Answer

ceil()

Answer

round()

Answer

prevint()

Question 3

What is the purpose of the 'tolower' function in C?

Accepted Answer

Converts a character to lowercase

Answer

Converts a character to uppercase

Answer

Removes leading spaces from a string

Answer

Converts a string to lowercase

Question 4

Which function is used to close a file in C?

Accepted Answer

fclose()

Answer

close()

Answer

endfile()

Answer

fileclose()

Question 5

What is the return value of the 'getchar' function in C?

Accepted Answer

The character read from the standard input

Answer

A random integer

Answer

-1

Answer

0

Question 6

Which library should be included to use the 'sin' function in C?

Accepted Answer

math.h

Answer

stdlib.h

Answer

cmath.h

Answer

algorithm.h

Question 7

What does the 'getch' function in C do?

Accepted Answer

Reads a character from the standard input without echoing

Answer

Reads a character from the standard input with echoing

Answer

Copies one string to another

Answer

Compares two strings

Question 8

What is the purpose of the 'toupper' function in C?

Accepted Answer

Converts a character to uppercase

Answer

Converts a character to lowercase

Answer

Removes trailing spaces from a string

Answer

Converts a string to uppercase

Question 9

Which function is used to find the square root of a number in C?

Accepted Answer

sqrt()

Answer

sqrtr()

Answer

sqrtroot()

Answer

squareroot()