GMAT Critical Reasoning (CR) | Re: Some say that an asteroid colliding with Earth was

Clearly A is the answer. In CR, author always believes his or her argument is air-tight. For example, if according to author A caused B, then nothing else but only A caused B. Similarly, if A did not cause B, then anything related to A did not cause B.

Using above logic, only A stands out as it clearly points out that something related to asteroid collision may have caused the death of surviving dinosaurs.

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