叠石是我国古代园林造景的基本要素。叠石一般用三种岩石，它们是太湖石、黄石和鹅卵石。( )
参考答案：错
A clean environment can help the city bid for the Olympics, _____ in turn will promote its economic
development. [ ]
A. what
B. which
C. that
D. as
