在下列横线处应添加的语句是( )。 class Base{public:void fun(){cout＜＜"Base::fun"＜＜end1;}}; class: Derived: public Base { public: void fun() { ______//显示调用基类的fun函数 cout＜＜"Derived::fun"＜＜end1; } };

A．Derived::fun

B．Base::fun();

C．Pubic::fun

D．fun();