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

[answerhappygod]

#include<stdio.h>
int recursive_sum_of_digits(int n)
{
if(n == 0)
return 0;
return n % 10 + recursive_sum_of_digits(n/10);
}
int main()
{
int n = 1201;
int ans = recursive_sum_of_digits(n);
printf("%d",ans);
return 0;
}
a) 6
b) 7
c) 5
d) 9