单项选择题

能将程序补充完整的选项是
class Person

private int a;
public int change(int m)return m;

public class Teacher extends Person

public int b;
public static void main(String arg[])

Person p=new Person();
Teacher t=new Teacher();
int i;
____

A.i=m
B.i=b
C.i=p.a
D.i=p.change(50)