His failure in the exam suggested that he the teacher’s instructions.
A. can’t have followed
B. needn’t have followed
C. mustn’t have followed
D. shouldn’t have followed
网友回答
(答案→)A. can’t have followed
B. needn’t have followed
C. mustn’t have followed
D. shouldn’t have followed
解析：can用于否定句和疑问句；肯定句中用may。