C Programming MCQs
Q.1 What will be the output of the following C code?
int main() {
int a = 10, b = 5;
printf(“%d”, a / b);
return 0;
}
A. 2
B. 5
C. 0
D. 10
Q.2 What is the output of the expression 2<3?
A. 0
B. 1
C. 2
D. 3
Q.3 What does the ‘!’ operator do in C?
A. Negation
B. Addition
C. Multiplication
D. None
Q.4 Which operator has higher precedence, ‘+’ or ‘*’?
A. *
B. Both are same
C. =+
D. None
Q.5 What does the ‘+’ operator do in C?
A. Addition
B. Subtraction
C. Multiplication
D. Division
Q.6 What is the result of the logical expression (1 && 0)?
A. 1
B. 0
C. True
D. False
Q.7 What does the ‘==’ operator check?
A. Assignment
B. Equality
C. Greater than
D. Less than
Q.8 Which operator is used for division in C?
A. –
B. *
C. /
D. =+
Q.9 Find the mistake in this code:
int main() {
float num;
printf(“Enter a number: “);
scanf(“%f”, num);
printf(“You entered: %f”, num);
return 0;
}
A. Missing & in scanf
B. Incorrect format specifier in printf
C. No error
D. Syntax error
Q.10 Identify the error in this C code:
int main() {
int x;
scanf(“%d”, x);
printf(“%d”, x);
return 0;
}
A. Missing & in scanf
B. Wrong format specifier
C. No error
D. Syntax error
Q.11 Pseudocode:
READ number PRINT “The number is “, number
What does this pseudocode do?
A. Reads and prints a number
B. Prints a fixed number
C. Generates a random number
D. None of these
Q.12 What will the following C code output?
int main() {
int num;
scanf(“%d”, &num);
printf(“%d”, num);
return 0;
}
A. The inputted number
B. %d
C. Syntax Error
D. Nothing
Q.13 What will be the output of the following C code?
int main() {
printf(“%d”, 500);
return 0;
}
A. 500
B. %d
C.. Syntax Error
D. None of these
Q.14 What does %d signify in the printf or scanf function?
A. Double data type
B. Decimal integer
C. Dynamic allocation
D. Directory path
Q.15 What is the purpose of the printf function in C?
A. To read input
B. To print output
C. To perform calculations
D. To control program flow
Q.16 Spot the error in this code snippet:
#include <stdio.h>
int main() {
const int age; age = 30;
printf(“%d”, age);
return 0;
}
A. Uninitialized constant
B. Missing return statement
C. Syntax error in printf statement
D. No error
Q.17 Identify the error in this C code:
int main() {
int number = 100.5;
printf(“%d”, number);
return 0;
}
A. Assigning float to int
B. Syntax error
C. No error
D. Wrong printf format
Q.18 What will be the output of the following C code?
int main() {
char c = ‘A’;
printf(“%d”, c);
return 0;
}
A. 65
B. A
C. Syntax Error
D. None of these
Q.19 What is the difference between ‘float’ and ‘double’ data types in C?
A. Syntax only
B. Precision
C. Usage
D. No difference
Q.20 What is the size of ‘int’ data type in C?
A. Depends on the system
B. 4 bytes
C. 8 bytes
D. 2 bytes
Q.21 Which of the following is a valid identifier in C?
A. 2ndName
B. _name
C. #name
D. none of these
Q.22 What data type would you use to store a character in C?
A. int
B. float
C. char
D. double
Q.23 Which of the following is not a keyword in C?
A. int
B. char
C. include
D. float
Q.24 Identify the error in this C program:
#include <stdio.h>
int main() {
print(“Hello, World!”);
return 0;
}
A. Missing #include statement
B. Incorrect function name
C. Syntax error in return statement
D. No error
Q.25 What will be the output of the following C program?
#include <stdio.h>
int main() {
printf(“Hello, World!”);
return 0;
}
A. Hello, World!
B. Syntax Error
C. 0
D. Nothing
Q.26 What is the primary purpose of writing a “Hello World” program when learning a new programming language?
A. To test if the language supports string operations
B. To learn complex programming concepts
C. To demonstrate basic syntax and output
D. To introduce advanced programming features
Q.27 How does a compiler differ from an interpreter?
A. A compiler executes code, while an interpreter does not
B. A compiler debugs code, while an interpreter does not
C. A compiler translates the entire program at once, while an interpreter translates it line by line
D. A compiler is used only in C programming, while an interpreter is not
Q.28 Which of the following is true about interpreters?
A. They execute programs faster than compilers
B. They translate the entire program at once
C. They translate and execute code line by line
D. They are not used in modern programming
Q.29 What is the main function of a compiler in programming?
A. To write code
B. To interpret code
C. To convert code into machine language
D. To debug code
Q.30 Why is learning programming important in today’s world?
A. For academic purposes only
B. To automate and solve complex problems
C. Only for software development
D. For entertainment purposes only
Q.31 What is the scope of a local variable in C?
A. Inside the function in which it is declared
B. Throughout the program
C. Inside the file
D. Throughout the function block where it is declared
Q.32 What is recursion in C?
A. A function calling another function
B. A function that has no return type
C. A function calling itself
D. A loop within a function
Q.33 What does ‘pass by value’ mean in C?
A. Passing a copy of the argument
B. Passing the argument directly
C. Passing the memory address
D. Passing the variable type
Q.34 What is the primary purpose of a function in C?
A. Code reuse and modularity
B. Error handling
C. Memory management
D. User interface creation
Q.35 Spot the mistake:
int main() {
for(int i = 0; i < 5; i++) {
if(i == 2)
continue;
printf(“%d “, i);
} return 0;
}
A. Infinite loop
B. Skips printing 2
C. Syntax error
D. No error
Q.36 Identify the error in this C code:
int main() {
int i = 0;
while(i < 3) {
i++;
}
printf(“%d “, i);
return 0;
}
A. Infinite loop
B. Syntax error
C. No error
D. Prints nothing
Q.37 SET i TO 0 WHILE i LESS THAN 10 IF i MOD 2 EQUALS 0 THEN CONTINUE INCREMENT i PRINT i END WHILE
A. Prints odd numbers from 1 to 9
B. Prints even numbers from 0 to 8
C. Prints all numbers from 0 to 9
D. Syntax error
Q.38 Pseudocode:
SET count TO 0 REPEAT PRINT count INCREMENT count UNTIL count EQUALS 3
A. Prints 0 1 2 3
B. Prints 0 1 2
C. Prints 3
D. Syntax error
Q.39 Pseudocode:
FOR i FROM 1 TO 5 PRINT i
A. Prints numbers from 1 to 5
B. Prints numbers from 1 to 4
C. Prints 5
D. Syntax error
Q.40 Pseudocode:
SET x TO 5 WHILE x GREATER THAN 0 DO PRINT x DECREMENT x
A. Prints numbers from 5 to 1 in descending order
B. Prints 5
C. Prints 0
D. Syntax error
Q.41 Pseudocode:
SET num TO 10 IF num EQUALS 10 THEN PRINT “Ten” ELSE PRINT “Not Ten”
A. Prints “Ten”
B. Prints “Not Ten”
C. Prints nothing
D. Syntax error
Q.42 What is the output of the following C code?
int main() {
int x = 0; do {
printf(“%d “, x);
x++;
} while(x < 3);
return 0;
}
A. 0 1 2
B. 0 1
C. 1 2 3
D. No output
Q.43 What does this C code do?
int main()
{ int i = 0;
while(i < 5) { if(i == 2) break;
printf(“%d “, i); i++; }
return 0;
}
A. Prints 0 1 2
B. Prints 0 1
C. Prints all numbers less than 5
D. Prints nothing
Q.44 What will the following C code print?
int main() {
for(int i = 0; i < 3; i++)
{ printf(“%d “, i); }
return 0;
}
A. 0 1 2
B. 1 2 3
C. 0 1 2 3
D. 1 2 3 4
Q.45 When is a do-while loop preferred over a while loop?
A. When the condition is complex
B. When the loop must execute at least once
C. When the loop should not execute
D. When the loop is infinite
Q.46 What is the purpose of the continue statement in loops?
A. Terminates the loop
B. Skips to the next iteration
C. Does nothing
D. Exits the program
Q.47 In a switch statement, what happens if a break statement is omitted from a case?
A. The program exits
B. The case is skipped
C. Fall-through to the next case
D. Syntax error
Q.48 What is the difference between for and while loops?
A. Syntax
B. Execution speed
C. Functionality
D. No difference
Q.49 What does the break statement do in a loop?
A. Exits the loop
B. Skips the current iteration
C. Repeats the loop
D. Does nothing
Q.50 Identify the mistake:
int main() {
int x = 10, y; y = x == 10 ? x : 0;
printf(“%d”, y);
return 0;
}
A. Incorrect use of ternary operator
B. Syntax error
C. No error
D. Wrong variable used
Q.51 Spot the error:
int main() {
int a = 10, b = 0;
printf(“%d”, a / b);
return 0;
}
A. Division by zero
B. Syntax error
C. No error
D. Wrong format specifier
Q.52 Pseudocode:
SET c TO 15 IF c MOD 2 EQUALS 0 THEN PRINT “Even” ELSE PRINT “Odd”
A. Prints “Even”
B. Prints “Odd”
C. Prints nothing
D. Syntax error
Q.53 Pseudocode:
SET x TO 5 IF x GREATER THAN 0 AND x LESS THAN 10 THEN PRINT “x is between 0 and 10”
A. Prints “x is between 0 and 10”
B. Prints nothing
C. Syntax error
D. Prints “x is not between 0 and 10”
Q.54 Pseudocode:
SET a TO 10, b TO 20 IF a GREATER THAN b THEN PRINT “a is greater” ELSE PRINT “b is greater or equal”
A. Prints “a is greater”
B. Prints “b is greater or equal”
C. Prints nothing
D. Syntax error
Q.55 Pseudocode:
SET value TO 10 PRINT NOT value
A. -10
B. 0
C. 1
D. 10
Q.56 Pseudocode:
SET num TO 5 IF num EQUALS 5 THEN PRINT “Five” ELSE PRINT “Not Five”
A. Prints “Five”
B. Prints “Not Five”
C. Prints nothing
D. Syntax error
Q.57 Pseudocode:
SET a TO 10, b TO 20 PRINT a PLUS b
A. 30
B. 20
C. 10
D. 0
Q.58 Pseudocode:
SET x TO 5, y TO 10 IF x LESS THAN y THEN PRINT “x is less than y” ELSE PRINT “x is not less than y”
A. Prints “x is less than y”
B. Prints “x is not less than y”
C. Prints nothing
D. Syntax error
Q.59 What is the result of the following expression?
int a = 1; int b = a++ + ++a;
A. 2
B. 3
C. 4
D. 5
Q.60 What is the output of the following C code snippet?
int main() {
int x
= 10;
printf(“%d”, x++ + ++x);
return 0;
}
A. 20
B. 21
C. 22
D. 23
Q.61 What is the output of sizeof(pointer) where pointer is an integer pointer in C?
A. 4 on all systems
B. 8 on all systems
C. Depends on the system architecture
D. Depends on the compiler
Q.62 What is a pointer in C?
A. A variable that stores a memory address
B. A function
C. An array
D. A data type
Q.63 Find the mistake:
int main() {
int arr[5] = {1, 2, 3, 4, 5};
for(int i = 0; i <= 5; i++) {
printf(“%d “, arr[i]);
}
return 0;
}
A. Off-by-one error in loop bounds
B. Syntax error
C. No error
D. Incorrect array initialization
Q.64 Identify the error in this C code:
int main() {
int arr[3];
arr[3] = 10;
printf(“%d”, arr[3]);
return 0;
}
A. Array index out of bounds
B. Syntax error
C. No error
D. Wrong printf format
Q.65 ARRAY matrix[2][3] SET matrix[0][0] TO 1, matrix[0][1] TO 2, matrix[0][2] TO 3, matrix[1][0] TO 4, matrix[1][1] TO 5, matrix[1][2] TO 6 PRINT matrix[1][2]
A. Prints 1
B. Prints 5
C. Prints 6
D. Syntax error
Q.66 Pseudocode:
FUNCTION SumArray(ARRAY arr, SIZE) SET sum TO 0 FOR i FROM 0 TO SIZE-1 INCREMENT sum BY arr[i] RETURN sum
A. Calculates the sum of array elements
B. Returns the size of the array
C. Returns the first element
D. Syntax error
Q.67 Pseudocode:
ARRAY arr[10] FOR i FROM 0 TO 9 SET arr[i] TO i TIMES 2 END FOR PRINT arr[6]
A. Prints 6
B. Prints 12
C. Prints 7
D. Syntax error
Q.68 Pseudocode:
ARRAY numbers[5] SET numbers[0] TO 1 PRINT numbers[0]
A. Prints 1
B. Prints 0
C. Prints random value
D. Syntax error
Q.69 Complete the C code:
int main() {
int arr[5];
for(int i = 0; i < 5; i++) { ___ }
printf(“%d”, arr[2]);
return 0;
}
A. arr[i] = i;
B. arr[i] = i * 2;
C. arr[i] = i + 1;
D. arr[i] = 0;
Q.70 What does the following C code do?
int main() {
int arr[3][4] = {{1, 2}, {3, 4}};
printf(“%d”, arr[1][1]);
return 0;
}
A. Prints 2
B. Prints 3
C. Prints 4
D. Prints 0
Q.71 What is the output of this C code?
int main() {
int arr[5] = {1, 2, 3};
printf(“%d”, arr[4]);
return 0;
}
A. 0
B. 3
C. Random value
D. Error
Q.72 What will be the output of the following C code?
int main() {
int arr[] = {1, 2, 3, 4, 5};
printf(“%d”, arr[3]);
return 0;
}
A. 1
B. 2
C. 3
D. 4
Q.73 In C, can an array be resized after its declaration?
A. Yes
B. No
C. Only if it’s a dynamic array
D. Only in C99 standard
Q.74 How does C handle array index out of bounds errors during runtime?
A. Generates a compile-time error
B. Automatically corrects the index
C. Generates a runtime error
D. Does not check for bounds
Q.75 What is the default value of an uninitialized array in C?
A. 0
B. 1
C. Random memory value
D. -1
Q.76 How can you access the third element in the second row of a 2D array int arr[3][4]; in C?
A. arr[1][2]
B. arr[2][3]
C. arr[3][2]
D. arr[2][1]
Q.77 What is the size of a 2-dimensional array int arr[3][4]; in C?
A. 3
B. 4
C. 12
D. Cannot be determined
Q.78 Which of the following is a correct way to pass an array to a function in C?
A. By specifying the size of the array
B. By passing the first element
C. By passing the array name
D. By passing each element individually
Q.79 How do you initialize an array in C?
A. With any value
B. With 0s
C. With 1s
D. Cannot be initialized
Q.80 What happens when you try to access an array element outside its bounds in C?
A. Syntax error
B. Compilation error
C. Runtime error
D. Undefined behavior
Q.81 Which index is used to access the first element of an array in C?
A. 0
B. 1
C. -1
D. First
Q.82 How do you declare an array of integers in C?
A. int arr[10];
B. array int[10];
C. int array 10;
D. [10]int array;
Q.83 Find the error:
int main() {
int x = 5;
increment(&x);
printf(“%d”, x);
return 0;
}
void increment(int* n) {
*n++;
}
A. Incorrect pointer usage in increment
B. Syntax error
C. No error
D. Wrong printf format
Q.84 Spot the mistake:
int main() {
int result = sum(5, 10);
printf(“%d”, result);
return 0;
}
int sum(int a, int b) {
return;
}
A. Missing return value in sum
B. Syntax error
C. No error
D. Incorrect function parameters
Q.85 Identify the error in this C code:
int main() {
printHello();
return 0;
}
void printHello() {
printf(“Hello”);
}
A. Missing declaration of printHello
B. Syntax error
C. No error
D. Wrong function call
Q.86 Pseudocode:
FUNCTION Fibonacci(n) IF n LESS THAN OR EQUAL TO 1 THEN RETURN n ELSE RETURN Fibonacci(n-1) PLUS Fibonacci(n-2) END FUNCTION CALL Fibonacci(5)
A. 5
B. 8
C. Error
D. None
Q.87 Pseudocode:
FUNCTION CheckEven(number) IF number MOD 2 EQUALS 0 THEN RETURN True ELSE RETURN False END FUNCTION CALL CheckEven(4)
A. True
B. False
C. Error
D. None
Q.88 Pseudocode:
FUNCTION Add(a, b) RETURN a PLUS b END FUNCTION CALL Add(5, 10)
A. 15
B. 5
C. 10
D. Error
Q.89 What is the output of this recursive function call?
int main() {
printf(“%d “, factorial(5));
return 0;
}
int factorial(int n) {
if (n==0)
return 1;
else
return n * factorial(n – 1);
}
A. 120
B. 24
C. 5
D. Error
Q.90 What will be the output of the following C code?
int main() {
int num = 10;
increment(num);
printf(“%d”, num);
return 0;
} void increment(int n) {
n++;
}
A. 10
B. 11
C. Error
D. Nothing
Q.91 What is a structure in C?
A. A collection of variables under a single name
B. A method for looping
C. A data type for characters
D. A control flow statement
Q.92 Spot the mistake:
int main() {
char *str = “Hello”;
str[0] = ‘M’;
printf(“%s”, str);
return 0;
}
A. Cannot modify a string literal
B. Syntax error
C. No error
D. Wrong printf format
Q.93 Identify the error in this C code:
int main() {
char str[] = “Hello”;
str[0] = ‘M’;
printf(“%s”, str);
return 0;
}
A. Cannot modify a string literal
B. No error
C. Syntax error
D. Wrong printf format
Q.94 Pseudocode:
FUNCTION CopyString(STRING source, STRING destination) FOR EACH character IN source SET destination TO source END FOR
A. Copies one string to another
B. Compares two strings
C. Concatenates two strings
D. Reverses a string
Q.95 Pseudocode:
FUNCTION FindChar(STRING str, CHAR ch) FOR EACH character IN str IF character EQUALS ch RETURN True END FOR RETURN False
A. Searches for a character in a string and returns true if found
B. Reverses the string
C. Concatenates the string
D. None of the above
Q.96 Pseudocode:
FUNCTION ConcatStrings(STRING str1, STRING str2) RETURN str1 PLUS str2 END FUNCTION
A. Concatenates two strings and returns the result
B. Finds the length of the two strings
C. Reverses the two strings
D. Compares the two strings
Q.97 What does the following C code do?
int main() {
char str1[] = “Hello”, str2[20];
strcpy(str2, str1);
strrev(str2);
printf(“%s”, str2);
return 0;
}
A. Copies str1 to str2 and reverses it
B. Concatenates str1 and str2
C. Compares str1 and str2
D. None of the above
Q.98 Complete the C code:
int main() {
char str[20];
___;
printf(“%s”, str);
return 0;
}
to copy “Hello” into str.
A. strcpy(str, “Hello”);
B. str = “Hello”;
C. strncpy(str, “Hello”, 5);
D. strcat(str, “Hello”);
Q.99 What is the output of this C code?
int main() {
char str[] = “Hello World”;
printf(“%d”, strlen(str));
return 0;
}
A. 11
B. 12
C. 10
D. Error
Q.100 What is the purpose of the strchr function in C?
A. Finds the first occurrence of a character in a string
B. Concatenates two strings
C. Reverses a string
D. Compares two strings
Q.101 How does the strncpy function differ from strcpy?
A. strncpy limits the number of characters copied
B. strncpy reverses the string
C. strncpy concatenates the string
D. No difference
Q.102 In C, which function is used to reverse a string?
A. strrev
B. strinvert
C. reverse
D. invert
Q.103 What happens if a string copied using strcpy is larger than the destination array?
A. Syntax error
B. Compilation error
C. Runtime error
D. Undefined behavior
Q.104 How do you declare an array of strings in C?
A. char *arr[];
B. string arr[];
C. char arr[][];
D. char **arr;
Q.105 What is the return value of strcmp when the two strings are equal in C?
A. 0
B. 1
C. -1
D. The length of the strings
Q.106 Which function is used to determine the length of a string in C?
A. strlen
B. strcmp
C. strncpy
D. strchr
Q.107 What does the strcat function do in C?
A. Concatenates two strings
B. Compares two strings
C. Converts a string to an integer
D. Splits a string into tokens
Q.108 What is the purpose of the strcpy function in C?
A. To compare two strings
B. To concatenate two strings
C. To copy one string to another
D. To find the length of a string
Q.109 How is a string represented in C?
A. As a series of characters followed by a null character
B. As an array of integers
C. As a single character
D. As a special data type
Q.110 Find the error:
int main() {
int arr[3] = {1, 2, 3};
int *p = arr;
printf(“%d”, *p + 2);
return 0;
}
A. Pointer arithmetic error
B. Syntax error
C. No error
D. Wrong printf format
Q.111 Spot the mistake:
int main() {
int a = 10, *p = &a;
*p++;
printf(“%d”, a);
return 0;
}
A. Incrementing a instead of *p
B. Syntax error
C. No error
D. Incorrect use of increment operator
Q.112 Identify the error in this C code:
int main() {
int *p; *p = 10;
printf(“%d”, *p);
return 0;
}
A. Uninitialized pointer
B. Syntax error
C. No error
D. Wrong printf format
Q.113 Pseudocode:
FUNCTION Increment(VALUE POINTER p) INCREMENT VALUE AT p END FUNCTION CALL Increment(ADDRESS OF num)
A. Increments num
B. Prints num
C. Returns num’s address
D. Error
Q.114 Pseudocode:
SET a TO 10, POINTER p TO ADDRESS OF a, PRINT VALUE AT p
A. Prints 10
B. Prints the address of a
C. Error
D. None of the above
Q.115 Complete the C code:
int main() {
int a = 10;
int *p = &a; ___;
printf(“%d”, a);
return 0;
}
to make the output 20.
A. *p = 20;
B. p = 20;
C. a = 20;
D. &a = 20;
Q.116 What does the following C code do?
int main() {
int arr[] = {1, 2, 3};
int *p = arr;
printf(“%d”, *(p + 1));
return 0;
}
A. Prints the first element of arr
B. Prints the second element of arr
C. Prints the third element of arr
D. Error
Q.117 What will be the output of the following C code?
int main() {
int a = 10;
int *p = &a;
printf(“%d”, *p);
return 0;
}
A. 10
B. Address of a
C. Error
D. 0
Q.118 How does dynamic memory allocation differ between malloc and calloc?
A. malloc initializes memory to zero, calloc does not
B. calloc initializes memory to zero, malloc does not
C. They don’t differ
D. malloc allocates more efficiently
Q.119 What does passing a pointer to a function allow the function to do?
A. Read the value of the variable
B. Change the value of the variable
C. Copy the variable
D. None of the above
Q.120 How do you access the value pointed to by a pointer in C?
A. Using the * operator
B. Using the & operator
C. Directly by the pointer name
D. Using the -> operator
Q.121 What is the use of the va_start, va_arg, and va_end macros in C?
A. They are used for file operations
B. They are used for memory allocation
C. They are used for handling variable arguments
D. They are used for error handling
Q.122 How can you access the individual command line arguments in a C program?
A. Using a for loop with argc and argv
B. Through global variables
C. By indexing into a predefined array
D. By calling a special function
Q.123 What is variable argument list in C, and which header file is required for it?
A. A list of arguments of variable types, stdlib.h required
B. A list of arguments of fixed types, stdio.h required
C. A list of arguments of variable length, stdarg.h required
D. A list of arguments of variable length, string.h required
Q.124 What is the purpose of argc in a C program?
A. To count the number of functions
B. To store environment variables
C. To count the number of command line arguments
D. To store error codes
Q.125 How are command line arguments passed to a C program?
A. Through global variables
B. Through function parameters
C. Through a dedicated command-line function
D. Through environment variables
Q.126 Spot the mistake:
#ifndef FILE_H #define FILE_H /* File contents */ #endif in a header file named “file.h”
A. The macro name should match the file name
B. No error
C. The header file name should be uppercase
D. The #ifndef and #define order is incorrect
Q.127 Identify the error in this C code snippet:
#include <stdio.h> #define MAX 100 #undef MAX int main() { printf(“%d”, MAX); return 0; }
A. Syntax error
B. Use of undefined MAX
C. No error
D. Incorrect usage of printf
Q.128 What happens when a header file is included twice in a C program without using include guards?
A. The program will not compile
B. The program compiles with warnings
C. The program compiles successfully, but it may cause errors
D. Nothing specific
Q.129 What is the result of using the #undef directive in C?
A. It deletes a file from the project
B. It removes a defined macro
C. It undefines a variable
D. It causes a compilation error
Q.130 How does the #ifndef directive function in C?
A. It checks if a variable is not defined
B. It imports a file if not previously imported
C. It checks if a macro is not defined
D. It defines a new macro if a condition is met
Q.131 What is the function of the #define directive in C?
A. To define a new function
B. To import a library
C. To define a macro or constant
D. To declare a variable
Q.132 What is the purpose of the #include directive in C?
A. To include a library during program execution
B. To declare a variable
C. To include a header file at compile time
D. To initialize variables
Q.133 Spot the mistake:
FILE *file = fopen(“example.bin”, “wb”); fwrite(&data, sizeof(data), 1, file); fclose(file);
A. Data should not be passed by reference in fwrite
B. fwrite arguments are in the wrong order
C. No error
D. File not opened in binary mode
Q.134 Identify the error in this C code for file writing:
FILE *file = fopen(“example.txt”, “w”); fprintf(file, “Hello World”); fclose(file);
A. Missing file mode in fopen
B. Incorrect usage of fprintf
C. No error
D. File not closed properly
Q.135 Complete the C code to read a binary file:
FILE *file = fopen(“example.bin”, “rb”); ___; fclose(file);
A. fread(buffer, sizeof(buffer), 1, file);
B. read(file, buffer, sizeof(buffer));
C. file >> buffer;
D. getline(file, buffer);
Q.136 What happens if you try to write to a file in C without opening it first?
A. The write operation succeeds with a warning
B. The write operation fails silently
C. An error occurs
D. The file is automatically created
Q.137 What is the purpose of the feof function in C?
A. To check if the end-of-file has been reached
B. To open a file
C. To read a file character by character
D. To write to a file
Q.138 How does file handling in binary mode differ from text mode in C?
A. Binary mode can read non-text files, text mode cannot
B. Binary mode is faster
C. Text mode translates newlines, binary mode does not
D. Text mode is more secure
Q.139 What function in C is typically used to open a file for reading or writing?
A. fopen()
B. open()
C. file_open()
D. stream()
Q.140 What is a stream in the context of C programming?
A. A sequence of characters
B. A type of data structure
C. A flow of binary data
D. A method of structuring code
Q.141 Spot the mistake:
struct Data { int val; }; int main() {
struct Data *ptr;
ptr->val = 100;
printf(“%d”, ptr->val);
return 0;
}
A. Uninitialized pointer used
B. Syntax error
C. No error
D. Wrong printf format
Q.142 Identify the error in this C code:
struct Point { int x, y; };
struct Point p1; p1.x = 10; p1.y = 20;
A. No error
B. Struct Point not properly declared
C. Struct members not properly accessed
D. Struct Point not properly instantiated
Q.143 Complete the C code:
union Data {
int i;
float f;
char str[20];
};
union Data data; ___;
printf(“%s”, data.str);
to store and print “Hello”.
A. data.str = “Hello”;
B. strcpy(data.str, “Hello”);
C. data = {.str = “Hello”};
D. data.str = {‘H’, ‘e’, ‘l’, ‘l’, ‘o’, ‘\0’};
Q.144 What does the following C code do?
struct Point {
int x, y;
};
struct Point p1 = {1, 2};
printf(“%d %d”, p1.x, p1.y);
A. Declares a structure and prints its members
B. Causes a syntax error
C. Initializes a structure but fails to print
D. None of the above
Q.145 What happens when a structure is passed to a function in C?
A. The entire structure is copied
B. Only the structure pointer is passed
C. The first element is passed
D. None of the above
Q.146 How are bit fields used in a structure in C?
A. To define the number of bits used by an integer type member
B. To encrypt data
C. To align data in memory
D. To define array sizes
Q.147 How can you instantiate a structure in C?
A. By using the new keyword
B. By declaring a variable of the structure type
C. By defining the structure with #define
D. By calling a function that returns a structure
Q.148 What is an enumerated data type in C?
A. A data type that allows numeric values only
B. A data type for storing lists of named constants
C. A special kind of array
D. A structure that can hold any data type
Q.149 What is the key difference between a structure and a union in C?
A. A structure can store multiple data types, a union cannot
B. A union can store multiple data types, a structure cannot
C. In a structure, only one member can be accessed at a time
D. In a union, only one member can be accessed at a time
Q.150 How do you access a member of a structure using a structure pointer in C?
A. With the dot operator (.)
B. With the arrow operator (->)
C. With the ampersand (&)
D. With the asterisk (*)
