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 consistency, answers should be in all lower cased letters.

Q: Category: INVESTING WITH WARREN BUFFETT 
Clue: Buffett calls the purchase of this insurance company one of his best investments; he first bought its stock in 1951

A: geico
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Q: Category: ROCKS & MINERALS 
Clue: A mixture containing antimony is sprayed on canvas to render it this

A: fireproof
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Q: Category: BOOKS & AUTHORS 
Clue: In a classic book, d'Artagnan hopes to serve as a guard to King Louis XIII & is befriended by this title group

A:
the three musketeers
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