เฉลย

1. c                                2. a             

3. b                                4. d             

5. a                                 6. b            

7. a                                8. a             

9. a                                10. a

11. b                               12. a  

13. c                               14. c  

15. a                                16. b 

17. c                                18. c  

19. c                                20. c

21. c                                22. b

23. b                               24. b

25. a                               26. b

27. d                               28. b

29. a                               30. b