按照买方权利划分，期权可以分为（）。
A.现货期权
B.期货期权
C.看涨期权
D.看跌期权
参考答案：C, D
— He is crazy about computer games.
— It isn't surprising _______ he isn't doing well in his study recently. [ ]
A. whether
B. that
C. why
D. what
制备薄荷水时加入滑石粉的作用是（）
A.助溶
B.增溶
C.助分散
D.助滤
E.助悬
