Consider the following iterative implementation used to reverse a string: #include #include void reverse_string(char *s) int len = strlen(s); int i,j; i=0; j=len-1; while(______) char tmp = s[i]; s[i] = s[j]; s[j] = tmp; i++; j--; Which of the following lines should be inserted to complete the above code?

Answer: Option D