GMAT Critical Reasoning (CR) | Re: When patients with clinical depression come to Royal Cornhill Mental

A. At least 60% of the patients who do not respond to the first treatment respond to some othertreatment.

We are only concerned about first treatment. Argument doesn't say anything about other treatment. So, can't be inferred.

B. At least 30% of the patients who do not respond to the first treatment do not respond to the subsequent treatments as well.

Last sentence of paragraph : More than 20 percent of depressed people respond to no treatment at all. We can safely say that around 30% that don't
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