【正确答案】 D

【答案解析】[解析] shouldn't have done sth. 意为“本来不应该做某事反而做了”，说明过去的动作，含有责备之意。Since he was very busy yesterday, you shouldn't have asked him for help. 他昨天很忙，你不该去找他帮忙。故D项为正确答案。A项和C项应用于现在时，而B项更强调本身的意愿，例如：With all this work on hand, you mustn't (oughtn't to) go to the cinema. 手头有这么多工作要做，你不可以(不应)去看电影。I have told him several times, but he wouldn't listen. 我告诉他好几次了，可他就是不听。