Explore topic-wise MCQs in C Programming.

This section includes 98 Mcqs, each offering curated multiple-choice questions to sharpen your C Programming knowledge and support exam preparation. Choose a topic below to get started.

1.

What would be the output of following program ?
int x = 15;
main()
{
 int x = 60;
 print(" n%d", x);
}
A. Error
B. 15
C. 60
D. Garbage value
Answer» D. Garbage value
Discussion
2.

Which of the following is the correct output for the program given below?
#include <studio.h>
int main()
{
 extern int x;
 x = 30;
 printf("%d n", sizeof(x));
 return 0;
}

A. 2
B. 4
C. Would vary from compiler to compiler
D. Error, x undefined
Answer» E.
Discussion
3.

Which of the following is the correct output for the program given below?
#include <studio.h>
int main()
{
 extern int k;
 printf("%d n", k );
 return 0;
}
int k = 30;
A. 30
B. 0
C. Garbage value
D. Error
Answer» B. 0
Discussion
4.

Which of the following is the correct output for the program given below ?
#include <studio.h>
int main()
{
 extern int fun (float);
 int k;
 k = fun (5.74);
 printf ("%d n", k);
 return 0;
}	
int fun (kk)
float kk;
 {
 return ((int) kk);
 }
A. 3
B. 5.74
C. 0
D. Error
Answer» E.
Discussion
5.

What will be the output of the following C code?
#include <stdio.h>
 void fun(const int *);
 int main()
 {
 const int k = 12;
 printf("%d ", k);
 fun(&k);
 printf("%d", k);
 
 }
 void fun(const int *k)
 {
 *k = 21;
 }
A. 12 21
B. 21 12
C. Runtime Error
D. Compilation Error
E. None of these
Answer» E. None of these
Discussion
6.

What will be the output of the following C code?
 #include <stdio.h>
 int main()
 {
 int Eighteen = 18;
 int eighteen = 15;
 printf("%d", eighteen);
 return 0;
 }
A. 18
B. Compilation Error
C. 15
D. Runtime Error
E. None of these
Answer» D. Runtime Error
Discussion
7.

Will the following C code compile without any error?
#include <stdio.h>
 int main()
 {
 int n;
 {
 int n;
 for (n = 0; n < 12; n++);
 }
 }
A. No
B. Yes
C. Depends on the C standard implemented by compilers
D. All of above
E. None of these
Answer» C. Depends on the C standard implemented by compilers
Discussion
8.

What will be the output of the following C code?
 #include <stdio.h>
 int main()
 {
 k = 23;
 printf("%d n", k++);
 return 0;
 }
A. 21
B. 22
C. 23
D. 24
E. Compilation Error
Answer» F.
Discussion
9.

What will be the output of the following C code?
#include <stdio.h>
 int main()
 {
 const int k = 11;
 int *p = &k;
 *p = 22;
 printf("%d n", k);
 return 0;
 }
A. 11
B. Compilation Error
C. 22
D. Runtime Error
E. None of these
Answer» D. Runtime Error
Discussion
10.

What will be the output of the following C code?
#include <stdio.h>
 void main()
 {
 int m = 12;
 float m = 12;
 printf("%d", m)
 }
A. 12
B. Compilation Error
C. 12.000000
D. Runtime Error
E. None of these
Answer» C. 12.000000
Discussion
11.

Will the following C code compile without any error?
#include <stdio.h>
 int main()
 {
 for (int n = 0; n < 5; n++);
 return 0;
 }
A. No
B. Yes
C. Garbage value
D. Depends on the C standard implemented by compilers
E. None of these
Answer» E. None of these
Discussion
12.

Which of the following format identifier can never be used for the variable var?
#include <stdio.h>
 int main()
 {
 char *variable = "Advanced Training in C by interviewmania.com";
 }
A. %s
B. %c
C. %d
D. %f
E. None of these
Answer» E. None of these
Discussion
13.

What will be the output of the following C code?
#include <stdio.h>
 int num;
 void main()
 {
 printf("%d", num);
 }
A. Compilation Error
B. 0
C. Runtime Error
D. Garbage value
E. None of these
Answer» C. Runtime Error
Discussion
14.

What will be the output of the following C code?
 #include <stdio.h>
 void main()
 {
 A();
 printf("%d", n);
 }
 int n;
 void A()
 {
 n = 10;
 }
A. 10
B. 0
C. Compilation Error
D. Depend on compiler
E. None of these
Answer» D. Depend on compiler
Discussion
15.

Which part of the program address space is p stored in the following C code?
#include <stdio.h>
 int *ptr;
 int main()
 {
 int n = 0;
 ptr = &n;
 return 0;
 }
A. Data segment
B. Code/text segment
C. Stack
D. Bss segment
Answer» E.
Discussion
16.

What will be the output of the following C code?
 #include <stdio.h>
 void main()
 {
 static int n;
 if (n++ < 5)
 main();
 }
A. 5
B. Infinite calls to main
C. Runtime Error
D. Varies
E. main is called twice
Answer» F.
Discussion
17.

What is the problem in following variable declaration?
float 2B-H-K?;
A. The special character -
B. The special character ?
C. The variable name begins with an integer
D. All of above
E. None of these
Answer» E. None of these
Discussion
18.

What will happen if the following C code is executed?
#include <stdio.h>
 int main()
 {
 int var = 15;
 printf("%d", var);
 return 0;
 }
A. 10
B. 12
C. 15
D. Compilation Error
E. None of these
Answer» D. Compilation Error
Discussion
19.

What is the output of this C code?
#include <stdio.h>
int main()
{
	printf("My Name is - %d  n", myName);
	return 0;
}
A. My Name is - myName;
B. My Name is - followed by a junk value
C. Compile time error
D. My Name is -
Answer» D. My Name is -
Discussion
20.

Which of the following is an external variable in the following C code?
 #include <stdio.h>
 int function(int p)
 {
 int q;
 return q;
 }
 int main()
 {
 int r;
 function(r);
 }
 int s;
A. p
B. q
C. r
D. s
E. None of these
Answer» E. None of these
Discussion
21.

What will be the output of the following C code?
#include <stdio.h>
 int n = 15;
 void main()
 {
 int n = 5;
 printf("%d ", n);
 {
 int n = 10;
 }
 printf("%d", n);
 }
A. 15 5
B. 5 15
C. 10 5
D. 5 10
E. 5 5
Answer» F.
Discussion
22.

What will be the output of the following C code?
#include <stdio.h>
 int num = 10;
 void main()
 {
 int num = 5;
 printf("%d ", num);
 {
 num = 6;
 }
 printf("%d", num);
 }
A. 10 5
B. 5 10
C. 6 5
D. 5 6
E. None of these
Answer» E. None of these
Discussion
23.

Which part of the program address space is ptr stored in the following C code?
#include <stdio.h>
 int *ptr = NULL;
 int main()
 {
 int n = 0;
 ptr = &n;
 return 0;
 }
A. 0
B. Code/text segment
C. Data segment
D. Bss segment
E. Stack
Answer» D. Bss segment
Discussion
24.

What will be the output of the following C code (after linking to source file having definition of arrayA)?
#include <stdio.h>
 int main()
 {
 extern arrayA[];
 printf("%d n", arrayA[0]);
 }
A. Compile time error due to multiple definitio
B. Compile time error because size of array is not provided
C. Compile time error because datatype of array is not provided
D. Value of arrayA[0];
E. None of these
Answer» D. Value of arrayA[0];
Discussion
25.

What will be the output of the following C code (without linking the source file in which arrayA is defined)?
#include <stdio.h>
 int main()
 {
 extern arrayA[];
 printf("Interview Mania n");
 }
A. Linking error due to undefined reference
B. Compile time error because datatype of array is not provided
C. Compile time error because size of array is not provided
D. Interview Mania
E. None of these
Answer» E. None of these
Discussion
26.

What will be the output of the following C code?
#include <stdio.h>
 int n;
 int main()
 {
 extern int n;
 if (p == 0)
 printf("Scope rules follow here n");
 }
A. Scope rules followed
B. Nothing will be printed as value of n is not zero because i is an automatic variable
C. Compile time error due to multiple declaration
D. Compile time error due to not defining type in statement extern n
E. None of these
Answer» B. Nothing will be printed as value of n is not zero because i is an automatic variable
Discussion
27.

What will be the output of the following C code?
 #include <stdio.h>
 void function();
 int main()
 {
 static int q = 25;
 function();
 }
 void function()
 {
 static int q;
 printf("%d", q);
 }
A. 25
B. Compilation Error
C. Runtime Error
D. 0
E. None of these
Answer» E. None of these
Discussion
28.

What will be the sequence of allocation and deletion of variables in the following C code?
#include <stdio.h>
 int main()
 {
 int num;
 {
 int var;
 }
 }
A. var->num, num->var
B. var->num, var->num
C. num->var, var->num
D. num->var, num->var
E. None of these
Answer» D. num->var, num->var
Discussion
29.

What will happen if the below program is executed?
#include <stdio.h>
int main()
{
 int main = 25;
 printf("%d", main);
 return 0;
}
A. It will cause a compile-time error
B. It will cause a run-time error
C. It will run without any error and prints
D. It will experience infinite looping
Answer» D. It will experience infinite looping
Discussion
30.

What will be the output of the following C code?
#include <stdio.h>
 int main()
 {
 register const int p = 16;
 p = 17;
 printf("%d n", p);
 }
A. Compilation Error
B. 17
C. 16
D. Garbage value
E. None of these
Answer» B. 17
Discussion
31.

Comment on the following 2 C Example programs.
#include <stdio.h> //Example 1
 int main()
 {
 int p;
 int q;
 int r;
 }
 
 #include <stdio.h> //Example 2
 int main()
 {
 int p;
 {
 int q;
 }
 {
 int r;
 }
 }
A. Scope of r is till the end of the main function in Example 2
B. In Example 1, variables p, q and r can be used anywhere in main function whereas in Example 2, variables q and r can be used only inside their respective blocks.
C. Both are same
D. Scope of p, q and r is till the end of the main function in Example 2.
E. None of these
Answer» C. Both are same
Discussion
32.

Which variable has the longest scope in the following C code?
#include <stdio.h>
 int p;
 int main()
 {
 int q;
 return 0;
 }
 int r;
A. p
B. q
C. r
D. both p and r
E. None of these
Answer» B. q
Discussion
33.

Comment on the output of the following C code.
#include <stdio.h>
 int main()
 {
 int k;
 for (k = 0; k < 10; k++)
 int m = k;
 printf("%d", m);
 }
A. Redeclaration of m in same scope throws error
B. Syntax error in declaration of m
C. m is out of scope when printf is called
D. No errors, program will show the output 15
E. None of these
Answer» C. m is out of scope when printf is called
Discussion
34.

What will be the output of the following C code?
#include <stdio.h>
 static int var = 51;
 void main()
 {
 int var = 91;
 {
 var = 41;
 }
 printf("%d", var);
 }
A. 51
B. 91
C. 41
D. Compilation Error
E. None of these
Answer» D. Compilation Error
Discussion
35.

What will be the output of the following C code?
#include <stdio.h>
 void main()
 {
 {
 int R = 81;
 }
 printf("%d", R);
 }
A. Undefined
B. Compilation Error
C. 81
D. Garbage value
E. None of these
Answer» C. 81
Discussion
36.

What will be the output of the following C code?
#include <stdio.h>
 int num;
 void main()
 {
 A();
 printf("%d", num);
 }
 void A()
 {
 num = 14;
 }
A. 14
B. 0
C. Undefined
D. Compilation Error
E. None of these
Answer» B. 0
Discussion
37.

What will be the output of the following C code?
 #include <stdio.h>
 int num = 15;
 void main()
 {
 int num = 13;
 A();
 printf("%d", num);
 }
 void A()
 {
 num = 18;
 B();
 }
 void B()
 {
 printf("%d ", num);
 }
A. 15 13
B. 13 15
C. 13 18
D. 18 13
E. None of these
Answer» E. None of these
Discussion
38.

What will be the output of the following C code?
#include <stdio.h>
 void main()
 {
 int num = 13;
 {
 num = 14;
 printf("%d", num);
 }
 }
A. 14
B. 13
C. Compilation Error
D. Runtime Error
E. None of these
Answer» B. 13
Discussion
39.

What will be the output of the following C code?
#include <stdio.h>
 void main()
 {
 static double s;
 int s;
 printf("s is %d", s);
 }
A. s is 0
B. Compilation Error
C. Runtime Error
D. Garbage value
E. None of these
Answer» C. Runtime Error
Discussion
40.

What will be the output of the following C code?
#include <stdio.h>
 static int num;
 void main()
 {
 int num;
 printf("num is %d", num);
 }
A. Runtime Error
B. num is 0
C. Compilation Error
D. Garbage value
E. None of these
Answer» C. Compilation Error
Discussion
41.

What will be the output of the following C code?
#include <stdio.h>
 void main()
 {
 static int R;
 printf("R is %d", R);
 }
A. Compilation Error
B. Runtime Error
C. Garbage value
D. R is 0
E. None of these
Answer» E. None of these
Discussion
42.

What will be the output of the following C code?
#include <stdio.h>
 void main()
 {
 fun();
 fun();
 }
 void fun()
 {
 static int R = 10;
 R++;
 printf("%d ", R);
 }
A. 10 11
B. 11 10
C. 12 11
D. 11 12
E. None of these
Answer» E. None of these
Discussion
43.

What will be the output of the following C code if these two files namely sample.c and sample1.c are linked and run?
 -------file sample.c-------
 #include <stdio.h>
 #include ""sample.h""
 int main()
 {
 n = 12;
 printf(""%d "", n);
 function();
 }
 
 -----file sample1.c------
 #include <stdio.h>
 #include ""sample.h""
 int function()
 {
 printf(""%d n"", n);
 }
 
 -----file sample.h-----
 #include <stdio.h>
 #include <stdlib.h>
 static int n;
A. 0 0
B. 0 12
C. 12 0
D. 12 12
E. None of these
Answer» D. 12 12
Discussion
44.

What will be the output of the following C code?
#include <stdio.h>
 int main()
 {
 register auto int num = 12;
 num = 13;
 printf("%d n", num);
 }
A. 12 13
B. 13 12
C. 12
D. 13
E. Compilation Error
Answer» F.
Discussion
45.

What will be the output of the following C code?
#include <stdio.h>
 int main()
 {
 register static int n = 13;
 n = 14;
 printf("%d n", n);
 }
A. Compilation Error
B. 13
C. 14
D. Runtime Error
E. None of these
Answer» D. Runtime Error
Discussion
46.

What will be the output of the following C code?
 #include <stdio.h>
 void main()
 {
 register int s;
 printf("%d", s);
 }
A. Garbage value
B. Compilation Error
C. Nothing
D. 0
E. None of these
Answer» E. None of these
Discussion
47.

What will be the output of the following C code?
#include <stdio.h>
 void main()
 {
 register int num = 10;
 if (num < 12)
 {
 num++;
 main();
 }
 }
A. main is called once
B. Segmentation fault
C. main is called thrice
D. main is called twice
E. None of these
Answer» C. main is called thrice
Discussion
48.

What will be the output of the following C code?
#include <stdio.h>
 register int p;
 void main()
 {
 printf("%d", p);
 }
A. 0
B. Garbage value
C. Compilation error
D. Varies
E. None of these
Answer» D. Varies
Discussion
49.

What will be the output of the following C code?
#include <stdio.h>
 int main()
 {
 auto R = 110;
 const auto int *ptr = &R;
 printf("%d n", R);
 }
A. Compilation Error
B. Garbage value
C. Depends on the compiler
D. Depends on the standard
E. 110
Answer» F.
Discussion
50.

What will be the output of the following C code?
#include <stdio.h>
 void function(auto int n);
 int main()
 {
 function(12);
 }
 void function(auto int n)
 {
 printf("%d n", n);
 }
A. Compilation Error
B. Depend on compiler
C. Depends on the standard
D. 12
E. None of these
Answer» B. Depend on compiler
Discussion