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

While it is obvious that A is the correct answer choice, it is important to understand why C is incorrect. If you take a look again and pay attention to the flow of the argument, you'll notice that the fact that several dinosaurs survived the impact and the subsequent temperature change is a premise, not an assumption. Without the surviving dinosaurs, there is no argument. Also, this fact is not even necessarily true - notice the word "perhaps" in the sentence.

Another way to look at
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