单选题 若有以下程序： #include ＜iostream＞ using namespace std; class Base { private: int x; protected: int y; public: int z; void setx(int i) { x=i; int getx () { return x; } }; class Inherit : private Base { private: int m; public: int p; void setvalue(int a, int b, intc, int d) { setx (A) ; y=b; z=c; m=d; } void display() { cout＜＜getx () ＜＜","＜＜y＜＜","＜＜z＜＜","＜＜m＜＜end1; } }; int main ( ) { Inherit A; A.setvalue(1,2,3,4); A.display (); return 0; }