请选择原文中划线部分在译文中处理为何种状语。All mater is made of atoms, which are too small to be seen even through the most powerful microscope.突然冷却的空气，由于挤出了部分水分，体积收缩，就变成了云。 ( ) A. 原因状语 B. 条件状语 C. 目的状语 D. 让步状语