执行如下程序将输出( ): #include<iostream> using namespace std; class Base public: Base()cout<< BB ;fun(); void fun ()tout<< Brim ; ; class Derived:public Base public: Derived()cout<< DD ; void fun ()cout<< Dfun ; ; int main()Derived d;return 0;
A.DD
B.BBDfunDDDfun
C.BBBfunDD
D.DDBBBfun