GMAT Critical Reasoning (CR) | RATT RACE: Provincial public safety experts have recorded a greater

I think the answer should be option C. My understanding of the problem :

There are two opinions presented here -- One of the author and the other of the expert. Our job is to weaken the stand of the author.

Premise : Amphibians in close proximity have higher instances of genetic mutation.

Expert's stand : Water from the coolant is responsible for genetic mutation, as it contains traces of radiation.

Author's stand : Some other reason behind genetic mutation. The author claims that though the
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