[求助]大全802

1.                             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 he air that forms them is moving rapidly, are（C）

(E) stationary crests and troughs although they are formed by rapidly moving air, is

请问E和C有什么区别，E错在什么地方？谢谢！

极有说服力！！

这是我看到的关于这题的最有说服力的理由！