【题目】____these experiments are interesting, it's important to remember that they may not always tell us much.
A.While
B.When
C.As
D.Since

【答案】A
【解析】句意：尽管这些实验有趣，但记住这一点很重要，那就是这些实验或许不会总告诉我太多。While“尽管/正当……时候”；When“当……时候”；As“因为/当……时候”；Since“既然/自从”。本句前后是转折关系，用转折连词。故选A。