Critical Reasoning (CR) | Re: Exposure to certain chemicals commonly used in elementary schools as

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GMATNinja firstly many kudos for your explanations, are always so informative!!

After reading your post I understood the reasoning for choosing (C), but I'd like your guidance to also clearly spot my mistake.

I chose (A) since I thought that the proportion we discuss is number of students with allergic reaction in this chemical to the number of nurses. Given from the question stem that the number of students sent to the hospital rises, based on the first choice, the number of nurses has either increased or remain stable. In the first case, the proportion will increase which answer our question and in the second one there would be no increase in the proportion so it's out of scope.

What am I missing?

Can anyone chip in?GMATCoachBen avigutman Bunuel chetan2u

Thanks in advance !
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