单项选择题

阅读下面程序:
public class ThreadTest
 public static void main(String args[]) throws Exception
  int i=0;
  Hello t=new Hello();
  ______;
  While(true)
   System.out.println("Good Morning"+i++);
   if(i==2&&t.isAlive())
    System.out.println("Main waiting for Hello!");
    t.join(); //等待t运行结束
   
   If(i==5)break:
  

class Hello extends Thread
  int i;
  public void run()
  while(true)
    System.out.println("Hello"+i++):
    If(i==5)break;
  
 

为使该程序正确执行,下画线处的语句应是

A.sleep()
B.yield()
C.interrupt()
D.start()