单选题

下面程序的输出结果是_________include using name...

Question

下面程序的输出结果是（）

#include <iostream>
using namespace std

class Base {
public:
    virtual void f() {
        cout << "f0+"
    }
    void g() {
        cout << "g0+"
    }
}
class Derived : public Base {
public:
    void f() {
        cout << "f+"
    }
    void g() {
        cout << "g+"
    }
}

int main() {
    Derived d
    Base* p = &d
    p->f()
    p->g()
    return 0
}

A. f+g+

B. f0+g+

C. f+g0+

D. f0+g0+