单项选择题

有如下程序
#include ＜iostream＞
using namespace std;
class basepublic:
virtual void f1()
cout＜＜"F1Base ";
virtual void f2()
cout＜＜"F2Base ";
;
class derive: public base void f1()
cout＜＜"F1Derive ";
void f2( int x )
cout＜＜"F2Derive ";
;
int main() base obj1, * p;
derive obj2;
p = & obj2;
p -＞ f1();
p -＞ f2();
return 0; 执行后的输出结果是