Critical Reasoning (CR) | Re: Climatologists believe they know why Earth has undergone a

For this type of problem statement, the correct answer is whichever choice does NOT support/strengthen the given argument. That choice could be something that weakens the argument; it could also just be something that has no effect on the argument at all (e.g., because it merely repeats something the argument already says, or because it's irrelevant altogether).

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