Explore topic-wise MCQs in C Interview.

This section includes 278 Mcqs, each offering curated multiple-choice questions to sharpen your C Interview knowledge and support exam preparation. Choose a topic below to get started.

1.

C Language developed at _________?

A. AT & T's Bell Laboratories of USA in 1972
B. AT & T's Bell Laboratories of USA in 1970
C. Sun Microsystems in 1973
D. Cambridge University in 1972
Answer» B. AT & T's Bell Laboratories of USA in 1970
Discussion
2.

For 16-bit compiler allowable range for integer constants is ________?

A. -3.4e38 to 3.4e38
B. -32767 to 32768
C. -32668 to 32667
D. -32768 to 32767
Answer» E.
Discussion
3.

C programs are converted into machine language with the help of

A. An Editor
B. A compiler
C. An operating system
D. None of these.
Answer» C. An operating system
Discussion
4.

C was primarily developed as

A. System programming language
B. General purpose language
C. Data processing language
D. None of the above.
Answer» B. General purpose language
Discussion
5.

What will be printed after execution of the following program code? main() { printf("\\nab"); printf("\\bsi"); printf("\\rha"); }

A. absiha
B. asiha
C. haasi
D. hai
Answer» E.
Discussion
6.

What number would be shown on the screen after the following statements of C are executed? char ch; int i; ch = 'G'; i = ch-'A'; printf("%d", i);

A. 5
B. 6
C. 7
D. 8
Answer» C. 7
Discussion
7.

Find the output of the following program. void main() { int i=01289; printf("%d", i); }

A. 0289
B. 1289
C. 713
D. Syntax error
Answer» E.
Discussion
8.

Find the output of the following program. void main() { int i=065, j=65; printf("%d %d", i, j); }

A. 53 65
B. 65 65
C. 065 65
D. 053 65
Answer» B. 65 65
Discussion
9.

What is the output of given program if user enter value 99? #include void main() { int i; printf("Enter a number:"); scanf("%d", &i); // 99 is given as input. if(i%5 == 0){ printf("nNumber entered is divisible by 5"); } }

A. Enter a number:99
B. Enter a number:99 Number is divisible by 5
C. compiler error
D. Run time error
Answer» B. Enter a number:99 Number is divisible by 5
Discussion
10.

What is the output of given program if user enter "xyz" ? #includevoid main() { float age, AgeInSeconds; printf("Enter your age:"); scanf("%f", &age); AgeInSeconds = 365 * 24 * 60 * 60 * age; printf("You have lived for %f seconds", AgeInSeconds);}

A. Enter your age: xyz You have lived for 0 seconds
B. Enter your age: xyz You have lived for 0.00000 seconds
C. Enter your age: xyz "after that program will stop"
D. Run time error
Answer» C. Enter your age: xyz "after that program will stop"
Discussion
11.

Which of the following statements are correct about the function? long fun(int num) { int i; long f=1; for(i=1; i

A. The function calculates the value of 1 raised to power num.
B. The function calculates the square root of an integer
C. The function calculates the factorial value of an integer
D. None of above
Answer» D. None of above
Discussion
12.

There is a error in the below program. Which statement will you add to remove it?#includeint main() { int a; a = f(10, 3.14); printf("%d\n", a); return 0; } float f(int aa, float bb) { return ((float)aa + bb); }

A. Add prototype: float f(aa, bb)
B. Add prototype: float f(int, float)
C. Add prototype: float f(float, int)
D. Add prototype: float f(bb, aa)
Answer» C. Add prototype: float f(float, int)
Discussion
13.

Which of the following statements are correct about the program?#includeint main() { printf("%p\n", main()); return 0; }

A. It prints garbage values infinitely
B. Runs infinitely without printing anything
C. Error: main() cannot be called inside printf()
D. No Error and print nothing
Answer» C. Error: main() cannot be called inside printf()
Discussion
14.

Point out the error in the program#includeint main() { int a=10; void f(); a = f(); printf("%d\n", a); return 0; } void f() { printf("Hi"); }

A. Error: Not allowed assignment
B. Error: Doesn't print anything
C. No error
D. None of above
Answer» B. Error: Doesn't print anything
Discussion
15.

Point out the error in the program#includeint f(int a) { a > 20? return(10): return(20); }int main() { int f(int); int b; b = f(20); printf("%d\n", b); return 0; }

A. Error: Prototype declaration
B. No error
C. Error: return statement cannot be used with conditional operators
D. None of above
Answer» D. None of above
Discussion
16.

Point out the error in the program f(int a, int b) { int a; a = 20; return a; }

A. Missing parenthesis in return statement
B. The function should be defined as int f(int a, int b)
C. Redeclaration of a
D. None of above
Answer» D. None of above
Discussion
17.

What will be the output of the program?#include#includeint main() { int i=0; i++; if(i

A. Prints "Study2Online" 5 times
B. Function main() doesn't calls itself
C. Infinite loop
D. Prints "Study2Online"
Answer» E.
Discussion
18.

What will be the output of the program?#includeint fun(int);int main() { float k=3; fun(k=fun(fun(k))); printf("%f\n", k); return 0; }int fun(int i) { i++; return i; }

A. 5.000000
B. 3.000000
C. Garbage value
D. 4.000000
Answer» B. 3.000000
Discussion
19.

What will be the output of the program?#includeint fun(int i) { i++; return i; }int main() { int fun(int); int i=3; fun(i=fun(fun(i))); printf("%d\n", i); return 0; }

A. 5
B. 4
C. Error
D. Garbage value
Answer» B. 4
Discussion
20.

What will be the output of the program?#includeint fun(int(*)());int main() { fun(main); printf("Hi\n"); return 0; }int fun(int (*p)()) { printf("Hello "); return 0; }

A. Infinite loop
B. Hi
C. Hello Hi
D. Error
Answer» D. Error
Discussion
21.

If int is 2 bytes wide.What will be the output of the program?#include void fun(char**);int main() { char *argv[] = {"ab", "cd", "ef", "gh"}; fun(argv); return 0; }void fun(char **p) { char *t; t = (p+= sizeof(int))[-1]; printf("%s\n", t); }

A. ab
B. cd
C. ef
D. gh
Answer» C. ef
Discussion
22.

What will be the output of the program?#includeint check(int);int main() { int i=45, c; c = check(i); printf("%d\n", c); return 0; }int check(int ch) { if(ch >= 45) return 100; else return 10; }

A. 100
B. 10
C. 1
D. 0
Answer» B. 10
Discussion
23.

What will be the output of the program?#includeint addmult(int ii, int jj) { int kk, ll; kk = ii + jj; ll = ii * jj; return (kk, ll); }int main() { int i=3, j=4, k, l; k = addmult(i, j); l = addmult(i, j); printf("%d, %d\n", k, l); return 0; }

A. 12, 12
B. 7, 7
C. 7, 12
D. 12, 7
Answer» B. 7, 7
Discussion
24.

What will be the output of the program?#includeint func1(int);int main() { int k=35; k = func1(k=func1(k=func1(k))); printf("k=%d\n", k); return 0; } int func1(int k) { k++; return k; }

A. k=35
B. k=36
C. k=37
D. k=38
Answer» E.
Discussion
25.

What will be the output of the program?#includeint i;int fun1(int);int fun2(int);int main() { extern int j; int i=3; fun1(i); printf("%d,", i); fun2(i); printf("%d", i); return 0; }int fun1(int j) { printf("%d,", ++j); return 0; } int fun2(int i) { printf("%d,", ++i); return 0; } int j=1;

A. 3, 4, 4, 3
B. 4, 3, 4, 3
C. 3, 3, 4, 4
D. 3, 4, 3, 4
Answer» C. 3, 3, 4, 4
Discussion
26.

What will be the output of the program?#includeint addmult(int ii, int jj) { int kk, ll; kk = ii + jj; ll = ii * jj; return (kk, ll); }int main() { int i=3, j=4, k, l; k = addmult(i, j); l = addmult(i, j); printf("%d %d\n", k, l); return 0; }

A. 12 12
B. No error, No output
C. Error: Compile error
D. None of above
Answer» B. No error, No output
Discussion
27.

What will be the output of the program?#includeint main() { int i=1; if(!i) printf("Study2Online,"); else { i=0; printf("C-Program"); main(); } return 0; }

A. prints "Study2Online, C-Program" infinitely
B. prints "C-Program" infinetly
C. prints "C-Program, Study2Online" infinitely
D. Error: main() should not inside else statement
Answer» C. prints "C-Program, Study2Online" infinitely
Discussion
28.

What will be the output of the program?#includeint fun(int, int); typedef int (*pf) (int, int); int proc(pf, int, int);int main() { printf("%d\n", proc(fun, 6, 6)); return 0; } int fun(int a, int b) { return (a==b); }int proc(pf p, int a, int b) { return ((*p)(a, b)); }

A. 6
B. 1
C. 0
D. -1
Answer» C. 0
Discussion
29.

What will be the output of the program?#includeint check (int, int);int main() { int c; c = check(10, 20); printf("c=%d\n", c); return 0; } int check(int i, int j) { int *p, *q; p=&i; q=&j; i>=45 ? return(*p): return(*q); }

A. Print 10
B. Print 20
C. Print 1
D. Compile error
Answer» E.
Discussion
30.

What will be the output of the program?#includeint main() { int fun(int); int i = fun(10); printf("%d\n", --i); return 0; }int fun(int i) { return (i++); }

A. 9
B. 10
C. 11
D. 8
Answer» B. 10
Discussion
31.

What will be the output of the program?#includeint main() { void fun(char*); char a[100]; a[0] = 'A'; a[1] = 'B'; a[2] = 'C'; a[3] = 'D'; fun(&a[0]); return 0; } void fun(char *a) { a++; printf("%c", *a); a++; printf("%c", *a); }

A. AB
B. BC
C. CD
D. No output
Answer» C. CD
Discussion
32.

What will be the output of the program?#includeint sumdig(int);int main(){ int a, b; a = sumdig(123); b = sumdig(123); printf("%d, %d\n", a, b); return 0; }int sumdig(int n) { int s, d; if(n!=0) { d = n%10; n = n/10; s = d+sumdig(n); } else return 0; return s; }

A. 4, 4
B. 3, 3
C. 6, 6
D. 12, 12
Answer» D. 12, 12
Discussion
33.

What will be the output of the program?#includevoid fun(int);typedef int (*pf) (int, int);int proc(pf, int, int);int main() { int a=3; fun(a); return 0; }void fun(int n) { if(n > 0) { fun(--n); printf("%d,", n); fun(--n); } }

A. 0, 2, 1, 0,
B. 1, 1, 2, 0,
C. 0, 1, 0, 2,
D. 0, 1, 2, 0,
Answer» E.
Discussion
34.

What will be the output of the program?#includeint reverse(int);int main(){ int no=5; reverse(no); return 0; }int reverse(int no) { if(no == 0) return 0; else printf("%d,", no); reverse (no--); }

A. Print 5, 4, 3, 2, 1
B. Print 1, 2, 3, 4, 5
C. Print 5, 4, 3, 2, 1, 0
D. Infinite loop
Answer» E.
Discussion
35.

What will be the output of the program? #includeint i;int fun();int main() { while(i) { fun(); main(); } printf("Hello\n"); return 0; } int fun() { printf("Hi"); }

A. Hello
B. Hi Hello
C. No output
D. Infinite loop
Answer» B. Hi Hello
Discussion
36.

What will be the output of the program? #includevoid fun(int*, int*);int main() { int i=5, j=2; fun(&i, &j); printf("%d, %d", i, j); return 0; } void fun(int *i, int *j) { *i = *i**i; *j = *j**j; }

A. 5, 2
B. 10, 4
C. 2, 5
D. 25, 4
Answer» E.
Discussion
37.

What will be the output of the program in 16 bit platform (Turbo C under DOS)?#includeint main() { int fun(); int i; i = fun(); printf("%d\n", i); return 0; } int fun() { _AX = 1990; }

A. Garbage value
B. 0 (Zero)
C. 1990
D. No output
Answer» D. No output
Discussion
38.

How many times the program will print "Study 2 Online" ? #include int main() { printf("Study 2 Online"); main(); return 0; }

A. Infinite times
B. 32767 times
C. 65535 times
D. Till stack overflows
Answer» E.
Discussion
39.

In which order do the following gets evaluated Relational Arithmetic Logical Assignment

A. 2134
B. 1234
C. 4321
D. 3214
Answer» B. 1234
Discussion
40.

Which of the following are unary operators in C? ! sizeof ~ &&

A. 1, 2
B. 1, 3
C. 2, 4
D. 1, 2, 3
Answer» E.
Discussion
41.

How many times "Study 2 Online" is get printed?#includeint main(){int x; for(x=-1; x

A. Infinite times
B. 11 times
C. 0 times
D. 10 times
Answer» D. 10 times
Discussion
42.

Can you combine the following two statements into one? char *p; p = (char*) malloc(100);

A. char p = *malloc(100);
B. char *p = (char) malloc(100);
C. char *p = (char*)malloc(100);
D. char *p = (char *)(malloc*)(100);
Answer» D. char *p = (char *)(malloc*)(100);
Discussion
43.

Is there any difference between following declarations?  extern int fun();  int fun();

A. Both are identical
B. No difference, except extern int fun(); is probably in another file
C. int fun(); is overrided with extern int fun();
D. None of these
Answer» C. int fun(); is overrided with extern int fun();
Discussion
44.

Which of the following is the correct order if calling functions in the below code?a = f1(23, 14) * f2(12/4) + f3();

A. f1, f2, f3
B. f3, f2, f1
C. Order may vary from compiler to compiler
D. None of above
Answer» D. None of above
Discussion
45.

Which of the datatypes have size that is variable?

A. int
B. struct
C. float
D. double
Answer» C. float
Discussion
46.

Which is correct with respect to size of the datatypes?

A. char > int > float
B. int > char > float
C. char < int < double
D. double > char > int
Answer» D. double > char > int
Discussion
47.

What is short int in C programming?

A. Basic datatype of C
B. Qualifier
C. short is the qualifier and int is the basic datatype
D. All of the mentioned
Answer» D. All of the mentioned
Discussion
48.

Which of the following cannot be a variable name in C?

A. volatile
B. true
C. friend
D. export
Answer» B. true
Discussion
49.

What is the problem in following variable declaration? float 3Bedroom-Hall-Kitchen?;

A. The variable name begins with an integer
B. The special character ‘-‘
C. The special character ‘?’
D. All of the mentioned
Answer» E.
Discussion
50.

Which is valid C expression?

A. int my_num = 100,000;
B. int my_num = 100000;
C. int my num = 1000;
D. int $my_num = 10000;
Answer» C. int my num = 1000;
Discussion