He the exam but he was too careless.A. could have passedB. couldn’t have passedC. must h

问题补充：

He the exam, but he was too careless.

A. could have passed

B. couldn’t have passed

C. must have passed

D. may have passed

答案：

(答案→)A. could have passed

B. couldn’t have passed

C. must have passed

D. may have passed

解析：此处could have passed the exam表示本能通过考试，实际上没有。句意：他本能通过考试的，但是他太粗心了。