【单选题】

下面程序段的输出结果是(      )。 

class Test{
public s，tatic void main(String args[]){
MyThread t=new MyThread()； 
t．displayOutput("t has been createD")； 
t．start()； 
}
}
Class MyThread extends Thread{
public void displayOutput(String s){
System．out．println(s)； 
}
public void run(){
displayOutput("t is running．")； 
}
}
A．t has been created． 
B．t has been created． t is running．
C．t is running．
D．编译出错