C Online Exam

Q1: What is the correct syntax to output 'Hello World' in C?

A) printf('Hello World');
B) System.out.println('Hello World');
C) echo 'Hello World';
D) console.log('Hello World');

Q2: What is the correct file extension for C programs?

A) .cp
B) .cpp
C) .c
D) .txt

Q3: Which symbol is used to comment a single line in C?

A) //
B) #
C) /* */
D) --

Q4: Which keyword is used to declare a variable in C?

A) var
B) int
C) let
D) declare

Q5: How do you declare a constant variable in C?

A) const int x;
B) constant x;
C) define x;
D) let x;

Q6: What is the default return type of the 'main' function in C?

A) float
B) void
C) char
D) int

Q7: Which of the following is not a valid data type in C?

A) int
B) float
C) bool
D) double

Q8: In C, which operator is used to allocate memory?

A) new
B) malloc
C) alloc
D) memory

Q9: How do you end a statement in C?

A) .
B) :
C) ;
D) /

Q10: What is the correct syntax for an if statement in C?

A) if { condition }
B) if (condition)
C) if condition
D) if condition {}

Q11: Which loop is guaranteed to execute at least once?

A) for
B) while
C) do...while
D) None

Q12: What is the size of int data type in C?

A) 2 bytes
B) 4 bytes
C) 8 bytes
D) Depends on the system

Q13: Which function is used to read a formatted input in C?

A) printf
B) scanf
C) input
D) read

Q14: How do you declare an array in C?

A) int[] arr;
B) int arr[10];
C) array arr[10];
D) arr{10};

Q15: What is the starting index of arrays in C?

A) 1
B) 0
C) -1
D) Depends on the array

Q16: Which function is used to find the length of a string in C?

A) strlen
B) length
C) size
D) strlength

Q17: What does 'EOF' stand for in C?

A) End of File
B) End of Function
C) Error on File
D) Exit on Failure

Q18: Which of the following is used to exit a loop in C?

A) continue
B) exit
C) break
D) stop

Q19: What is a pointer in C?

A) A variable that stores a memory address
B) A function
C) A type of loop
D) A structure

Q20: How do you access a value from a pointer?

A) *p
B) &p
C) p*
D) p&

Q21: Which header file is required for using printf and scanf functions?

A) stdio.h
B) stdlib.h
C) conio.h
D) math.h

Q22: What is the purpose of the return statement in C?

A) To break a loop
B) To return a value from a function
C) To end a program
D) To call another function

Q23: Which operator is used to get the address of a variable?

A) *
B) &
C) %
D) @

Q24: What is a function prototype in C?

A) A function call
B) A function declaration
C) A function definition
D) None of the above

Q25: Which function is used to allocate memory dynamically in C?

A) malloc
B) alloc
C) calloc
D) Both malloc and calloc

Q26: Which of the following loops in C does not use a condition to stop?

A) for
B) while
C) do...while
D) infinite loop

Q27: What is the maximum value of an unsigned int in C (assuming 4 bytes)?

A) 2^31 - 1
B) 2^32 - 1
C) 2^30 - 1
D) 2^16 - 1

Q28: What is the difference between '==' and '=' in C?

A) Both are same
B) '==' is assignment, '=' is comparison
C) '=' is assignment, '==' is comparison
D) None of the above

Q29: Which keyword is used to create a structure in C?

A) struct
B) object
C) class
D) structure

Q30: How do you define a macro in C?

A) #define
B) macro
C) let
D) #macro

Q31: Which function terminates the execution of a program in C?

A) end
B) stop
C) return
D) exit

Q32: Which is the logical AND operator in C?

A) &&
B) ||
C) &
D) |

Q33: What will be the output of 'printf("%d", 5+3*2);'?

A) 16
B) 11
C) 13
D) 10

Q34: Which keyword is used to avoid duplicate inclusions of a header file?

A) #include_once
B) #pragma once
C) include guard
D) #header

Q35: What is the value of the expression '5/2' in C?

A) 2
B) 2.5
C) 3
D) None of the above

Q36: How do you initialize a variable to zero in C?

A) int x=0;
B) x=0;
C) int x;
D) int x=1;

Q37: What is the output of 'printf("%d", 3==3);'?

A) 3
B) 0
C) 1
D) Error

Q38: Which keyword is used for creating an infinite loop in C?

A) for
B) while
C) do...while
D) All of the above

Q39: How do you declare a floating-point variable in C?

A) float x;
B) real x;
C) double x;
D) float var;

Q40: Which header file is required for using the sqrt function?

A) stdio.h
B) math.h
C) stdlib.h
D) conio.h

Q41: What does 'NULL' represent in C?

A) Zero
B) Empty pointer
C) Nothing
D) None of the above

Q42: How do you call a function in C?

A) call function();
B) function()
C) call function;
D) function{};

Q43: Which operator is used for modulus in C?

A) /
B) *
C) %
D) #

Q44: How do you define a union in C?

A) union
B) class
C) object
D) struct

Q45: What does 'sizeof' return in C?

A) Size in bytes
B) Size in bits
C) Size in KB
D) Size in MB

Q46: How do you declare a character array in C?

A) char arr[];
B) string arr[];
C) char[] arr;
D) character arr[];

Q47: What does the function 'strcmp' do in C?

A) Concatenate strings
B) Copy strings
C) Compare strings
D) None of the above

Q48: What will be the output of 'printf("%c", 'a' + 1);'?

A) a
B) b
C) c
D) None of the above

Q49: How do you open a file for writing in C?

A) fopen('file', 'w');
B) fwrite('file');
C) fileopen('file', 'w');
D) open('file', 'w');

Q50: What does 'fclose' do in C?

A) Opens a file
B) Closes a file
C) Deletes a file
D) None of the above