GMAT Critical Reasoning (CR) | Re: A certain cultivated herb is one of a group

Histidine production over the life cycle is not related to the conclusion. The conclusion is whether Histidine is the factor that allows these planst to survive in metal rich soils.

Option B:
Answer "yes": If other closely related plants (who grow in metal rich soils) also produce Histidine, then Histidine could be the factor for the survival of these plants in metal rich soils.
Answer "no":
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