My little son used to drink a lot of fruit juice but these days he mineral waterA. prefer

问题补充：

My little son used to drink a lot of fruit juice but these days he mineral water．

A. prefers

B. is preferring

C. preferred

D. had preferred

答案：

(答案→)A. prefers

B. is preferring

C. preferred

D. had preferred

解析：考查时态。根据句意可知这是一个过去与现在的对比。后面的these days说明本题应该使用现在时表示目前的情况。