1．【答案】A

2．【答案】C

3．【答案】B

4．【答案】C

5．【答案】C

6．【答案】A

7．【答案】C

8．【答案】D

9．【答案】D

10．【答案】D

11．【答案】B

12．【答案】D

13．【答案】C

14．【答案】A

15．【答案】B

16．【答案】D

17．【答案】A

18．【答案】D

19．【答案】A

20．【答案】A