Explore topic-wise MCQs in C Programming.

This section includes 65 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.

Would the following work?

A. Yes
B. No
Answer» C.
Discussion
2.

Preprocessor directive can be used only on a macro that has been earlier

A. True
B. False
Answer» B. False
Discussion
3.

There exists a way to prevent the same file from getting twice in the same program.

A. True
B. False
Answer» B. False
Discussion
4.

Will the following program print the message infinite number of times?

A. Yes
B. No
Answer» B. No
Discussion
5.

Preprocessor directive .. ... is used for conditional compilation.

A. True
B. False
Answer» B. False
Discussion
6.

Will the program compile successfully?

A. Yes
B. No
Answer» B. No
Discussion
7.

Which of the following are correct preprocessor directives in C?

A. 1, 2
B. 4
C. 1, 2, 4
D. 1, 2, 3, 4
Answer» E.
Discussion
8.

Which of the following are correctly formed statements in C?

A. #define CUBE (X) (X*X*X);
B. #define CUBE(x) (X*X*X)
C. #define CUBE(X)(X*X*X)
D. #define CUBE(X) {X*X*X}
Answer» D. #define CUBE(X) {X*X*X}
Discussion
9.

What will the SWAP macro in the following program be expanded to on preprocessing? will the code compile?

A. It compiles
B. Compiles with an warning
C. Not compile
D. Compiles and print nothing
Answer» D. Compiles and print nothing
Discussion
10.

In which stage the following code gets replaced by the contents of the file

A. During editing
B. During linking
C. During execution
D. During preprocessing
Answer» E.
Discussion
11.

Will the following program print the message infinite number of times?_x000D_ #include_x000D_ #define INFINITELOOP while(1)_x000D_ _x000D_ int main()_x000D_ {_x000D_ INFINITELOOP_x000D_ printf("IndiaBIX");_x000D_ return 0;_x000D_ }

A. Yes
B. No
Answer» B. No
Discussion
12.

What will be the output of the program? #include_x000D_ #define FUN(arg) do\_x000D_ {\_x000D_ if(arg)\_x000D_ printf("IndiaBIX...", "\n");\_x000D_ }while(--i)_x000D_ _x000D_ int main()_x000D_ {_x000D_ int i=2;_x000D_ FUN(i

A. IndiaBIX... IndiaBIX... IndiaBIX
B. IndiaBIX... IndiaBIX...
C. Error: cannot use control instructions in macro
D. No output
Answer» C. Error: cannot use control instructions in macro
Discussion
13.

What will be the output of the program?_x000D_ #include_x000D_ #define MAN(x, y) ((x)>(y)) ? (x):(y);_x000D_ _x000D_ int main()_x000D_ {_x000D_ int i=10, j=5, k=0;_x000D_ k = MAN(++i, j++);_x000D_ printf("%d, %d, %d\n", i, j, k);_x000D_ return 0;_x000D_ }

A. 12, 6, 12
B. 11, 5, 11
C. 11, 5, Garbage
D. 12, 6, Garbage
Answer» B. 11, 5, 11
Discussion
14.

Point out the error in the program #include_x000D_ _x000D_ int main()_x000D_ {_x000D_ int i;_x000D_ #if A_x000D_ printf("Enter any number:");_x000D_ scanf("%d", &i);_x000D_ #elif B_x000D_ printf("The number is odd");_x000D_ return 0;_x000D_ }

A. Error: unexpected end of file because there is no matching #endif
B. The number is odd
C. Garbage values
D. None of above
Answer» B. The number is odd
Discussion
15.

What will the SWAP macro in the following program be expanded to on preprocessing? will the code compile?_x000D_ #include_x000D_ #define SWAP(a, b, c)(c t; t=a, a=b, b=t)_x000D_ int main()_x000D_ {_x000D_ int x=10, y=20;_x000D_ SWAP(x, y, int);_x000D_ printf("%d %d\n", x, y);_x000D_ return 0;_x000D_ }

A. It compiles
B. Compiles with an warning
C. Not compile
D. Compiles and print nothing
Answer» D. Compiles and print nothing
Discussion
16.

What will be the output of the program?_x000D_ #include_x000D_ #define SWAP(a, b) int t; t=a, a=b, b=t;_x000D_ int main()_x000D_ {_x000D_ int a=10, b=12;_x000D_ SWAP(a, b);_x000D_ printf("a = %d, b = %d\n", a, b);_x000D_ return 0;_x000D_ }

A. a = 10, b = 12
B. a = 12, b = 10
C. Error: Declaration not allowed in macro
D. Error: Undefined symbol 't'
Answer» C. Error: Declaration not allowed in macro
Discussion
17.

The output of the following program is:#define f(g,g2) g##g2void main(){int var12=100;printf("%d", f(var,12));}

A. yntax error
B. untime error
C. ##g2
D. 00
E. 0012
Answer» E. 0012
Discussion
18.

What will be output after executing following code?#include# define a 10void main(){printf("%d..", a);foo();printf("%d", a);}void foo(){#undef a#define a 50}

A. 0..50
B. 0..10
C.
Answer» C.
Discussion
19.

What will be the output of the following program?#include#define prod(a,b)a*bvoid main(){int x=3,y=4;printf("%d", prod(x+2,y-1));}

A. 5
B. 2
C. 0
D. 1
E. one of these
Answer» D. 1
Discussion
20.

Choose the correct statement.I.The scope of a macro definition need not be the entire program.II.The scope of a macro definition extends from the point of definition to the end of the file.III. New line is a macro definition delimiter.IV.A macro definition may go beyond a line.

A. and II
B. I and III
C. , II and III
D. I, III and IV
E. , II, III and IV
Answer» F.
Discussion
21.

What will be the output of the program code?#include#define a 10void main(){#define a 50printf("%d", a);}

A. 0
B. 0
C. ompiler Error
D. one of These
Answer» B. 0
Discussion
22.

What will be the output of the program?#include#define int charvoid main(){int i = 65;printf("sizeof(i)=%d", sizeof(i));}

A. izeof(i)=2
B. izeof(i)=1
C. ompiler Error
D. one of These
Answer» C. ompiler Error
Discussion
23.

Once preprocessing is over and the program is sent for the compilation the macros are removed from the expanded source code.

A. 1
B.
Answer» B.
Discussion
24.

A header file contains macros, structure declaration and function prototypes.

A. 1
B.
Answer» B.
Discussion
25.

What will be the output of the program? #include #define MESS junk int main() { printf("MESS\n"); return 0; }

A. junk
B. MESS
C. Error
D. Nothing will print
Answer» C. Error
Discussion
26.

What will be the output of the program? #include #define FUN(i, j) i##j int main() { int va1=10; int va12=20; printf("%d\n", FUN(va1, 2)); return 0; }

A. 10
B. 20
C. 1020
D. 12
Answer» C. 1020
Discussion
27.

Preprocessor directive #ifdef .. #else ... #endif is used for conditional compilation.

A. 1
B.
Answer» B.
Discussion
28.

What will be the output of the program? #include #define str(x) #x #define Xstr(x) str(x) #define oper multiply int main() { char *opername = Xstr(oper); printf("%s\n", opername); return 0; }

A. Error: in macro substitution
B. Error: invalid reference 'x' in macro
C. print 'multiply'
D. No output
Answer» D. No output
Discussion
29.

A preprocessor directive is a message from compiler to a linker.

A. 1
B.
Answer» C.
Discussion
30.

Every C program will contain at least one preprocessor directive.

A. 1
B.
Answer» C.
Discussion
31.

Macros have a local scope.

A. 1
B.
Answer» C.
Discussion
32.

What will be the output of the program? #include #define PRINT(i) printf("%d,",i) int main() { int x=2, y=3, z=4; PRINT(x); PRINT(y); PRINT(z); return 0; }

A. 2, 3, 4,
B. 2, 2, 2,
C. 3, 3, 3,
D. 4, 4, 4,
Answer» B. 2, 2, 2,
Discussion
33.

What will be the output of the program? #include #define FUN(arg) do\ {\ if(arg)\ printf("IndiaBIX...", "\n");\ }while(--i) int main() { int i=2; FUN(i

A. IndiaBIX... IndiaBIX... IndiaBIX
B. IndiaBIX... IndiaBIX...
C. Error: cannot use control instructions in macro
D. No output
Answer» C. Error: cannot use control instructions in macro
Discussion
34.

The preprocessor can trap simple errors like missing declarations, nested comments or mismatch of braces.

A. 1
B.
Answer» C.
Discussion
35.

Macros with arguments are allowed

A. 1
B.
Answer» B.
Discussion
36.

What will be the output of the program? #include #define MAX(a, b) (a > b ? a : b) int main() { int x; x = MAX(3+2, 2+7); printf("%d\n", x); return 0; }

A. 8
B. 9
C. 6
D. 5
Answer» C. 6
Discussion
37.

What will be the output of the program? #include #define MAX(a, b, c) (a>b ? a>c ? a : c: b>c ? b : c) int main() { int x; x = MAX(3+2, 2+7, 3+7); printf("%d\n", x); return 0; }

A. 5
B. 9
C. 10
D. 3+7
Answer» D. 3+7
Discussion
38.

Will it result in to an error if a header file is included twice?

A. Yes
B. No
C. It is compiler dependent.
Answer» D.
Discussion
39.

What will be the output of the program? #include #define SWAP(a, b) int t; t=a, a=b, b=t; int main() { int a=10, b=12; SWAP(a, b); printf("a = %d, b = %d\n", a, b); return 0; }

A. a = 10, b = 12
B. a = 12, b = 10
C. Error: Declaration not allowed in macro
D. Error: Undefined symbol 't'
Answer» C. Error: Declaration not allowed in macro
Discussion
40.

It is necessary that a header files should have a .h extension?

A. Yes
B. No
Answer» C.
Discussion
41.

A macro must always be defined in capital letters.

A. 1
B.
C. 1
D.
Answer» C. 1
Discussion
42.

What will be the output of the program? #include #define JOIN(s1, s2) printf("%s=%s %s=%s \n", #s1, s1, #s2, s2); int main() { char *str1="India"; char *str2="BIX"; JOIN(str1, str2); return 0; }

A. str1=IndiaBIX str2=BIX
B. str1=India str2=BIX
C. str1=India str2=IndiaBIX
D. Error: in macro substitution
Answer» C. str1=India str2=IndiaBIX
Discussion
43.

What will be the output of the program? #include #define SQR(x)(x*x) int main() { int a, b=3; a = SQR(b+2); printf("%d\n", a); return 0; }

A. 25
B. 11
C. Error
D. Garbage value
Answer» C. Error
Discussion
44.

What will be the output of the program? #include #define MIN(x, y) (x 0) printf("%d\n", z); return 0; }

A. 3
B. 4
C. 0
D. No output
Answer» B. 4
Discussion
45.

What will be the output of the program? #include #define CUBE(x) (x*x*x) int main() { int a, b=3; a = CUBE(b++); printf("%d, %d\n", a, b); return 0; }

A. 9, 4
B. 27, 4
C. 27, 6
D. Error
Answer» D. Error
Discussion
46.

Will the program compile successfully? #include int main() { #ifdef NOTE int a; a=10; #else int a; a=20; #endif printf("%d\n", a); return 0; }

A. Yes
B. No
Answer» B. No
Discussion
47.

What will be the output of the program? #include #define PRINT(int) printf("int=%d, ", int); int main() { int x=2, y=3, z=4; PRINT(x); PRINT(y); PRINT(z); return 0; }

A. int=2, int=3, int=4
B. int=2, int=2, int=2
C. int=3, int=3, int=3
D. int=4, int=4, int=4
Answer» B. int=2, int=2, int=2
Discussion
48.

Will the program compile successfully? #include int main() { printf("India" "BIX\n"); return 0; }

A. Yes
B. No
Answer» B. No
Discussion
49.

Which of the following are correctly formed #define statements in C?

A. #define CUBE (X) (X*X*X);
B. #define CUBE(x) (X*X*X)
C. #define CUBE(X)(X*X*X)
D. #define CUBE(X) {X*X*X}
Answer» D. #define CUBE(X) {X*X*X}
Discussion
50.

Would the following typedef work? typedef #include l;

A. Yes
B. No
Answer» C.
Discussion