Question

The cost of living in Chengdu is among the lowest in China, ________ the quality of life is probably
one of the highest.

A．since

B．when

C．as

D．while

Answer 1

D

解析试题分析: 句意：成都的消费水平是中国最低中一个，而生活质量可能是最高中的一个。since  自从，when   当……时， as  正如，while而；根据lowest和highest，可知为意思转折，故选D.
考点：考查并列句。