--- May I visit you at 10 o’clock tomorrow morning?
--- I’m afraid I a document for my boss then. What about 12:00?
A. am preparing
B. will have prepared
C. will be preparing
D. have been preparing
网友回答
A. am preparing
B. will have prepared
(答案→)C. will be preparing
D. have been preparing
解析：考查时态：句意：--明天早上10点我可以去看你吗？--恐怕那时我正为老板准备论文呢。12点怎样？说明准备论文的动作是明天早上10点正在做，用将来进行时。选C。