單項(xiàng)選擇題 1. public interface A {
2. public void doSomething(String thing);
3. }
1. public class AImpl implements A {
2. public void doSomething(String msg) { }
3. }
1. public class B {
2. public A doit() {
3. // more code here
4. }
5.
6. public String execute() {
7. // more code here
8. }
9. }
1. public class C extends B {
2. public AImpl doit() {
3. // more code here
4. }
5.
6. public Object execute() {
7. // more code here
8. }
9. }
Which statement is true about the classes and interfaces in the exhibit?()