单选题 有如下程序：
#include ＜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;
}
执行这个程序的输出结果是______。