(单选题)11: public class X extends Frame{
public static void main(String[] args){
X x=new X();x.pack();x.setVisible(true);
}
public X(){
setLayout(new GridLayout(2,2));
Panel p1=new Panel(); add(p1);
Button b1
A: all change height and width
B: Button One change height
C: Button Two change height and Button Three change width
D: Button Four change height and width
