How many times is the function recursive_reverse_string() called when the following code is executed?

#include<stdio.h>
#include<string.h>
void recursive_reverse_string(char *s, int left, int right)
{
     if(left < right)
     {
         char tmp = s[left];
         s[left] = s[right];
         s[right] = tmp;
         recursive_reverse_string(s, left+1, right-1);
     }
}
int main()
{
     char s[100] = "madam";
     int len = strlen(s);
     recursive_reverse_string(s,0,len-1);
     printf("%s",s);
     return 0;
}

A. 3

B. 4

C. 5

D. 6

Answer: Option A