private cars are bringing us convenience, they may also cause traffic accidents
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private cars are bringing us convenience, they may also cause traffic accidents and pollution.
A.When
B.Since
C.while
D.As
试题答案
C
句意:尽管私人车辆给我们带来了方便，然而他们也可能引起了交通事故和污染。while虽然，尽管。所以选C。