【题目】She looks very happy. She_________ the exam.
A.can have passedB.should have passedC.must have passedD.could have passed
在线课程【答案】C
【解析】
考查情态动词。句意；她看起来很高兴。她一定通过了考试。must /could+ have done表示对过去发生的事情的推测，意为“一定/可能（已经）… ”，本句中根据语境She looks very happy可判断，用 must have passed语气较强，意为“一定是已经通过了（考试）”，故排除D项，选C。