1．【答案】A

2．【答案】D

3．【答案】C

4．【答案】C

5．【答案】B

6．【答案】C

7．【答案】B

8．【答案】A

9．【答案】D

10．【答案】B

11．【答案】A

12．【答案】B

13．【答案】B

14．【答案】D

15．【答案】B

16．【答案】B

17．【答案】A

18．【答案】B

19．【答案】D

20．【答案】C