You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For simplicity, answers should be in all lower cased letters.
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Question: Category: HISTORIC QUOTES
Clue: This great Prussian king is credited with saying, "An army, like a serpent, travels on its belly"

Answer: frederick the great

Question: Category: BRITISH AUTHORS
Clue: This 19th C. novelist's name gave us an adjective that's used to mean squalid or impoverished

Answer: charles dickens

Question: Category: A "CY" OF RELIEF
Clue: If this monster of Greek mythology had an eye on you, that was all the eyes he had

Answer:
cyclops