如下代码创建一个新线启动线程: MyThread target=new MyThread(); Thread myThread=new Thread(target); 问:如下哪些类不可以创建target对象并编译正确?( ) A. public class MyThread extends Runnable { public void run(){} } B. public class MyThread extends Thread { public void run() {} } C. public class MyThread implements Runnable {public void run() {}} D. public class MyThread implements Thread {void run() {}}