--Shelooksveryhappy.She       havepassedtheexam.--Igues...

问题详情：

--She looks very happy. She        have passed the exam.

--I guess so. It’s not difficult after all.

A. should          B. could           C. must            D. might

【回答】

知识点：虚拟语气与情态动词

题型：选择题