【题目】Tell your friend not to take the pills _______ he may have health problems in the future, _______ it is too late.
A.cause; which
B.that; when
C.because; when
D.that; which

【答案】C
【解析】句意：让你朋友不要吃这些药片，因为这些药片来可能引起健康方面的问题，到时候就太迟了。because引导原因状语从句，表因果关系；when引导定语从句，在从句中作状语。