⟩ program Output #include <iostream> using namespace std; class sample { public sample(int i) m_i(i) { } public int operator()(int i = 0) const { return m_i + i; } operator int () const { return m_i; } private int m_i; friend int g(const sample&); }; int f(char c) { return c; } int main() { sample f(2); cout << f(2); return 0; } a) 3 b) 4 c) 5 d) None of the mentioned