Consider the following recursive implementation to find the factorial of a number. Which of the lines should be inserted

[answerhappygod]

int fact(int n)
{
if(_________)
return 1;
return n * fact(n - 1);
}
int main()
{
int n = 5;
int ans = fact(n);
printf("%d",ans);
return 0;
}
a) n = 0
b) n != 0
c) n == 0
d) n == 1