What is the output of this recursive C++ function?

#include <iostream>
using namespace std;
int fun(int n)
{
    if (n == 1)
        return 1;
    return n * fun(n - 1);
}
int main()
{
    cout << fun(5);
    return 0;
}
                        

Options

• A. 15
• B. 25
• C. 120
• D. More than one of the above
• E. None of the above