Which two statements are true?

Given:

11. public class PingPong implements Runnable {
12. synchronized void hit(long n) {
13. for(int i = 1; i < 3; i++)
14. System.out.print(n + “-” + i + ” “);
15. }
16. public static void main(String[] args) {
17. new Thread(new PingPong()).start();
18. new Thread(new PingPong()).start();
19. }
20. public void run() {
21. hit(Thread.currentThread().getId());
22. }
23. }

Which two statements are true? (Choose two.)

A.
The output could be 8-1 7-2 8-2 7-1

B.
The output could be 7-1 7-2 8-1 6-1

C.
The output could be 8-1 7-1 7-2 8-2

D.
The output could be 8-1 8-2 7-1 7-2