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.

Q: Category: BESTSELLERS 
Clue: "Gettysburg", cowritten by this former House speaker, imagines a Confederate victory at Gettysburg

A: newt gingrich
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Q: Category: ART & ARTISTS 
Clue: An X-ray of his "Blue Boy" has revealed the figure of a small dog that was painted out

A: thomas gainsborough
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Q: Category: SPORTS VENUES 
Clue: John L. Sullivan was the first heavyweight champ to box in this original venue; in 1971, Joe Frazier beat Ali there

A:
madison square garden
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