GMAT Reading Comprehension (RC) | Re: Micro-wear patterns found on the teeth of long-extinct specimens

Walker's theory is that "a" (australopithecine) were fruit eaters because they had "indistinguishable" tooth micro-wear characteristics from orangutans, who "are commonly assumed to be[fruit eaters] ."

His theory would be called into question if this correlation was somehow inaccurate or not conclusive. Hence the word "assumed to be" because they are not entirely certain that this is accurate.

A)
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