Critical Reasoning (CR) | Rainwater contains hydrogen of a heavy form called deuterium. The deut

Option A says "A) There is little deuterium in the North American caves than the deuterium in the water trapped there."This means other than the Deuterium that is available in the trapped rain water in the caves, there is not much (or no) deuterium from other sources.

Firstly, we want some explanation that tells us why the deuterium in caves is lesser than that in the trees, or
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