Critical Reasoning (CR) | Several ancient Greek texts provide accounts of people being

The question is the assumption. The question alone does not offer any type, but the stem tells that the first sentence is the conclusion. Surely, boiled down to B, and D.
Test takers should know that both B and D are two common patterns in gmat.
B is wrong b/c it talks about the non-poison, and B just shows a correlation.
D is the gap between the premise and the conclusion.

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