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


i narrowed down the answer to be btw C and E ns finally went 4 E as it is succinctly written...but the OG is [spoiler]c
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