若有以下程序: #include <iostream> using namespace std; class A { private:int x; protected:int y; public:int z;void setx(int i){ x=i;}int getx (){ return x; }; class B : protected A { public:void setvalue(int a, int b, int c){ setx (a); y=b; z=c;}void display(){ cout<<getx ( ) <<", "<<y<<", "<<z<<", "<<end1;} }; int main () {B obj;obj.setvalue(5, 6, 7);obj.display ( );return 0; } 程序运行后的输出结果是( )。
A.产生语法错误
B.7,6,5
C.5,6,7
D.7,5,6