【题目】______ the environmental impacts of larger plastics are well documented, very little is understood about the dangers associated with micro plastics.
A.WhileB.AsC.BecauseD.If
在线课程【答案】A
【解析】
考查让步状语从句。句意：虽然较大的塑料对环境的影响已有详细记录，但对于微塑料的危害却知之甚少。A. While 尽管；B. As由于；C. Because因为；D. If如果。此处是while“尽管”引导的让步状语从句。故选A。