we stood at the top of the building we were able to enjoy the town below clearly.A. AsB.

问题补充：

we stood at the top of the building，we were able to enjoy the town below clearly.

A. As

B. Although

C. Unless

D. Until

答案：

(答案→)A. As

B. Although

C. Unless

D. Until

解析：句意：由于我们站在楼顶上，我们能够清楚地看到下面的整座城市。由句意可知，两个句子之间是因果关系，所以用A项。