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

IMO C
Option A tells that the number of nurse has been constant , but they have received more number of allergic students.
This increase is due to increase in the number of enrollment of the students.
Option B does not help either as it talks about allergies to other substances.
Option D also does not tells about the quantity of allergic substance or the children becoming more sensitive.
Option E actually is negation of the argument .

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