单项选择题

有如下程序:
#nclude <iostream>
using namespace std;
class Base public:
void fun1() cout << "Base\n";
virtual void fun2() cout << "Base\n";
;
class Derived: public Base public:
void fun1() cout << "Derived\n";
void fun2() cout << "Derived\n"; void f(Base& b) B. fun1(); B. fun2();
int main()Derived obj;
f(obj);
return 0;

A.Base
Base
B.Base
Derived
C.Derived
Base
D.Derived
Derived