单项选择题 A class games.cards.Poker is correctly defined in the jar file Poker.jar.  A user wants to execute the main method of Poker on a UNIX system using the command：  java games.cards.Poker  What allows the user to do this？（）

单项选择题 1. public class GC {  2. private Object o；  3. private void doSomethingElse（Object obj） { o = obj； }  4. public void doSomething（） {  5. Object o = new Object（）；  6. doSomethingElse（o）；  7. o = new Object（）；  8. doSomethingElse（null）；  9.o=null；  10. }  11. }  When the doSomething method is called， after which line does the Object created in line 5 become available for garbage collection？（）

单项选择题 11. class Snoochy {  12. Boochybooch；  13. public Snoochy（） { booch = new Boochy（this）； }  14. }  15.  16. class Boochy {  17. Snoochy snooch；  18. public Boochy（Snoochy s） { snooch = s； }  19. }  And the statements：  21. public static void main（String[] args） {  22. Snoochy snoog = new Snoochy（）；  23. snoog = null；  24. // more code here  25. }  Which statement is true about the objects referenced by snoog， snooch， and booch immediately after line 23 executes？（）