What will be the output of the following C++ code?

#include <iostream>  
using namespace std;
int f(int &x, int c) 
{
   c  = c - 1;
   if (c == 0) return 1;
   x = x + 1;
   return f(x, c) * x;
} 
int main(int argc, char const *argv[])
{
	int a = 4;
	cout<<f(a,a);
	return 0;
}

A. A variable that stores the size of another variable B. A variable that stores the address of another variable C. A variable that stores a reference to another variable D. None of the above

A. ptr *type; B. type ptr; C. type *ptr; D. ptr type;

A. Address of x B. Garbage value C. Compilation error D. 5

A. *ptr B. ptr* C. &ptr D. ptr