He ______ full marks, but he was so careless as to make a spelling mistake.[      ]

A. must have gained

B. can have gained

C. could have gained

D. must gain

明确说明“癥即积，瘕即聚”的医著是（）。

A.《景岳全书》

B.《医宗必读》

C.《杂病广要》

D.《外台秘要》

E.《丹溪心法》