GMAT Critical Reasoning (CR) | Re: A new study provides more support for the hypothesis that

Here is my approach.

Lets identify the cause and effect in the argument.

Cause: Social isolation

Effect: Weaker immune system

Based on this cause-effect relationship, the argument concludes that social support strengthens immune system.

So the conclusion basically assumes that if cause is removed (or social support is improved), then the effect will be reversed (immune system will be strengthened).

Hence C is the answer.

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