Which function is used to concatenate two strings in C?

• strcat()
• concat()
• strjoin()
• stringconcat()

#include <stdio.h> int main() { char str1[] = "Hello"; char str2[] = "World"; strcat(str1, str2); printf("%s", str1); return 0; }

• "HelloWorld"
• "WorldHello"
• "Hello"
• "World"

Which library must be included to use string functions in C

• <stdlib.h>
• <string.h>
• <math.h>
• <stdio.h>

#include <stdio.h> int main() { char str[] = "C Language"; printf("%s", str + 2); return 0; }

• Prints "Language"
• Prints "C Language"
• Causes a compilation error
• Results in a runtime error

#include <stdio.h> int main() { char str[] = "Hello"; str[0] = 'J'; printf("%s", str); return 0; }

• "Hello"
• "Jello"
• "H"
• Causes a compilation error

#include <stdio.h> int main() { char str1[] = "Hello"; char str2[] = "Hello"; int result = strcmp(str1, str2); printf("%d", result); return 0; }

• Prints 0
• Prints 1
• Prints -1
• Causes a compilation error

#include <stdio.h> int main() { char str[] = "Hello"; printf("%c", str[strlen(str) - 1]); return 0; }

• 'o'
• H'
• l'
• e'

#include <stdio.h> int main() { char str[] = "Hello"; printf("%d", str[0]); return 0; }

• Prints 'H'
• Prints 72
• Causes a compilation error
• Results in a runtime error

#include <stdio.h> int main() { char str[] = "Programming"; printf("%s", str + 5); return 0; }

• "Programming"
• "amming"
• "ramming"
• "ammingming"

#include <stdio.h> #include <string.h> int main() { char str1[] = "Hello"; char str2[] = "Hello"; int result = strncmp(str1, str2, 3); printf("%d", result); return 0; }

• Prints 0
• Prints 1
• Prints -1
• Causes a compilation error