CP #6

From GMATHacks.com

Bipedal dinosaurs' standing posture differs from virtually every visual depiction of them created before the 1970s, when scientists reevaluated their assumptions about tripod-style balance.
(A)	Bipedal dinosaurs' standing posture differs from
(B)	Bipedal dinosaurs stood in a posture that differs from
(C)	Bipedal dinosaurs exhibited standing postures that differ from those of
(D)	The standing posture of bipedal dinosaurs differs from
(E)	The characteristics of bipedal dinosaurs' standing posture differ from those of

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Answer: C

The words "differ from" signal that there is a comparison. In this case, the comparison is between the actual posture of dinosaurs and the posture as depicted by certain images. As written, the sentence is incorrect: it compares the actual standing posture with "every visual depiction." We can't compare a posture with a picture as those are unlike things.

Choice (B) makes the same mistake, comparing a posture with pictures. (C) makes a proper comparison between "standing postures" and "those of." The word "those" takes the place of "standing postures," so we're comparing the actual standing postures with the standing postures as depicted. (D) makes the same mistake as (A) and (B). (E) is complicated but is yet another comparison error. It compares characteristics of standing posture with "those" (characteristics) of visual depictions. Those are different things, so (C) must be correct.