There is a new problem involved in the popularity of private cars ________ road

题型：不详难度：来源：

There is a new problem involved in the popularity of private cars ________ road conditions need ________.

A．that；to be improved	B．which; to be improved
C．where；improving	D．when；improving

答案

A

解析

　因为“公路状况需要改善”，“need”后接“improving”或“to be improved”都可以。后面的从句应是“problem”的同位语，应用“that”引导。