单项选择题
Tom is the man who always does （） best even in the most difficult situation.
A. one's B. your C. their D. his
单项选择题 The question came up at the meeting （） we had enough money for our re- search.
单项选择题 He doesn't smoke now, but he（）two years ago.
单项选择题 -- How much is your new computer （）-- 12,000 Yuan.
