单项选择题

下面程序的结果是( )。    #include<iostream.h>    class test{ private:          int num;        public:         test( );         int getint( ) {return num;}         ~test( );};    test::test( )    { num=0;}    test::~test( )    { cout<<"Destructor is active"<<endl;}    void main( )    { test x[3];      cout<<"Exiting main"<<endl;}

A.信息隐藏
B.数据封装
C.定义新类
D.数据抽象