单选题 _____ the right answer I would have got full marks in the exam.无
【正确答案】 C
【答案解析】句意:如果我知道正确答案,我考试就会得满分了。本题考查的是虚拟语气的用法,由主句的would have done可知,该题考查的是与过去相反的事实,故从句要用had done,但是从句省略了if,就得把had提前,故答案为C。