单选题 He said ______ was not within his power to answer the question.
【正确答案】 D
【答案解析】[考点] 宾语从句
[解析] 由题干可知宾语从句中缺少主语，而宾语从句中的真正主语是to answer the question。因此要用it来充当形式主语。故选D。