When if he hadany idea what the novel was about, Jack kept silent. He have read it very carefully.
A. asking; needn't
B. asking; shouldn't
C. asked; can’t
D. asked; mustn’t
网友回答
A. asking; needn't
B. asking; shouldn't
(答案→)C. asked; can’t
D. asked; mustn’t
解析：原句意思是当被问及他认为这部小说写了些什么，杰克就保持沉默。谓语动词ask和主语Jack是被动关系。needn't have done 表示过去做了不必做的事情shouldn’t have done 本不该做某事can’t have done 表示对过去某种情况的怀疑或不确定mustn’t have done禁止做，故选C，最符合题意。