Critical Reasoning (CR) | Geologist: The dominant view that petroleum formed from the fossilized

Geologist: The dominant view that petroleum formed from the fossilized remains of plants and animals deep in the earth's crust has been challenged by scientists who hold that it formed, not from living material, but from deep carbon deposits dating from the formation of the earth. But their theory is refuted by the presence in petroleum of biomarkers, molecules indicating the past or present existence of a living organism.

Which one of the following, if true, most weakens the geologist's argument?

(A)
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