95. The peaks of a mountain range, acting like rocks in a streambed, produce ripples in the air flowing over them; the resulting flow pattern, with crests and troughs that remain stationary although the air that forms them is moving rapidly, are known as “standing waves.” (A) crests and troughs that remain stationary although the air that forms them is moving rapidly, are (B) crests and troughs that remain stationary although they are formed by rapidly moving air, are (C) crests and troughs that remain stationary although the air that forms them is moving rapidly, is (D) stationary crests and troughs although the air that forms them is moving rapidly, are (E) stationary crests and troughs although they are formed by rapidly moving air, is
正确答案是C 我的疑问在于E为什么错。 OG的解释是: E. The subordinate clause in the passive voice following although is awkward and unclear