【正确答案】 C

【答案解析】[解析] 虚拟语气用在条件句中表示对过去的假设，从句使用过去完成时，主句使用“would (should，could，might) +have done”，例如：If the facts had been collected earlier, we would have had more time to study them. 如果这些材料早些时候搜集到，我们就会有更多的时间对其进行研究了。If I had answered the policemen seriously, I would not have been arrested. 如果我认真地回答警察的问题，就不会被逮捕了。