the temperature falling so rapidly we couldn't go on with the experience.A. SinceB. With

问题补充：

the temperature falling so rapidly, we couldn go on with the experience.

A. Since

B. With

C. As

D. For

答案：

A. Since

(答案→)B. With

C. As

D. For

解析：此句中含有一个用with引导的独立分词结构，在句子中做状语。since,as和for三个词在表示“因为，由于”这一概念时，均是连词，其后要用完整的句子，不可只跟短语。