He lives in a __ building,There is a ___ table in his room.

A．ten-ground, three-leg

B．ten-stories, three-legs

C．ten-storeyed; three-legged

D．ten-storeym three-leg

河流侵蚀基准面下降，使河水的侵蚀能力增强的作用方式是（）。

A、下蚀作用

B、侧蚀作用

C、单向环流作用

D、双向环流作用