单项选择题

有如下程序:
#include<iostream>using namespace std;class Point{public: static int number;public: Point(){number++;} ~Point(){number--;}};int Point::number=0;void main(){ Point*ptr; Point A,B; { Point*ptr_point=new Point[3]; ptr=pb_point; } Point C cout<<Point::number<<endl; delete[]ptr; }
运行时输出的结果是()。

A.3
B.4
C.6
D.7