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

Option E talks about the proportion of children wrt. to the entire population of the city. The increase proportion could mean either the number of children is more and the population is same as before OR the population of the city has lessened when the number of children is same as before.
This gives us nothing to show that these children are getting exposed to more chemicals than before. Hence E is out.

I hope this helps some one.

---