Which one of the following C++ string functions returns a pointer to the first occurrence of x in string y? strcat(x,y) strcpy(x, y) O strstr(x, y) strcmp(x, y) Question 13 Not yet answered Marked out of 1.00 Flag question Which one of the following is a conditional macro which will work when the main conditional macro fails #elseif o #endit O #else O #it