Last week I took the Civil Service Admission Examination, for which I for nearly three months．
A. had prepared
B. would prepare
C. was preparing
D. have been preparing
网友回答
(答案→)A. had prepared
B. would prepare
C. was preparing
D. have been preparing
解析：考查时态。句意为上个星期我参加了公务员考试，为了这次考试我已经准备了三个月了。根据句意可知准备了三个月发生在考试之前，故选择过去的过去。