19.2658答案：C

20.2776答案：C

21.2778答案：B

22.2779答案：D

23.2795答案：D

24.2796答案：B

25.2941答案：B

26.2942答案：D

27.2943答案：C

28.2960答案：C

29.2961答案：B

30.2962答案：C

31.2963答案：C

32.3013答案：C

33.3022答案：D

34.3023答案：C

35.3204答案：B

36.3206答案：A

37.3205答案：C

38.1912答案：C