-Pity you missed the lecture on nuclear pollution.-- I it but was busy preparing

问题补充：

---- Pity you missed the lecture on nuclear pollution.

---- I it, but was busy preparing for a job interview.

A. would have attended

B. had attended

C. would attend

D. attended

答案：

(答案→)A. would have attended

B. had attended

C. would attend

D. attended

解析：这是两个人之间的对话。第一个人说：“很遗憾你错过了核污染的讲座。” 第二个人说： “我本打算去的，但是忙于一次工作面试”。对过去情况的虚拟，主句用“ would/ should/ might/ could + have + 过去分词，所以选A。