It was clear that the alcohol had seriously  impaired  Anderson's sense of reality.

A. weakened

B. impressed

C. enhanced

D. strengthened

【答案解析】本题正确选项A。译文：显然，酒精严重削弱了安德森对真实的感觉。解析：题中画线词impair意为“减少、削弱”；在四个备选项中，weaken意为“削弱”；impress意为“铭记、留下印象”；enhance意为“加强”；strengthen意为“强化”。这里需要选择和画线词impair相近的词，因此，依据题意在四个选项中最符合题意的选项是A。