Which of the following function is used to find the first occurrence of a given string in another string?ans.

The function used to find the first occurrence of a given string in another string is the strstr() function in C. Here's how you can use it:

1. Include the string library in your program using #include <string.h>.

2. Declare your main strings and the substring you want to find.

3. Use the strstr() function. It takes two arguments: the main string and the substring. The function will return a pointer to the first occurrence of the substring in the main string.

Here's a simple example:

#include <string.h>
#include <stdio.h>

int main () {
   const char haystack[20] = "TutorialsPoint";
   const char needle[10] = "Point";
   char *ret;

   ret = strstr(haystack, needle);

   printf("The substring is: %s\n", ret);

   return(0);
}

In this example, strstr() will return a pointer to the first occurrence of "Point" in "TutorialsPoint". The output will be: "The substring is: Point".