若有以下程序: #include 〈iostream〉 using namespace std; class A { private:int x; public:int z;void setx(int i){ x=i;}int getx (){ return x;} }; class B : public A { private:int m; public:int p;void setvalue(int a,int b, int C){ setx (A) ; z=b; m=c;}void display(){ cout〈〈getx()〈〈","〈〈z〈〈","〈〈m〈〈end1;} }; int main ( ) {B obj;obj.setvalue(2,3,4);obj.display();return 0; } 程序运行以后的输出结果是( )。
A.产生语法错误
B.2,3,4
C.2,2,2
D.4,3,2