GMAT Critical Reasoning (CR) | Re: Early pencil leads were made of solid graphite

Early pencil leads were made of solid graphite mined in Cumberland, in Britain. Modern methods of manufacturing pencil leads from powdered graphite are the result of research sponsored by the government of France in the 1790s, when France was at war with Britain and thus had no access to Cumberland graphite.
Type - Inference

(A) The world’s only deposit of graphite suitable for manufacture of pencils is in Cumberland, Britain. - Incorrect - this may or may not be true. There might be other
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