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: WHAT A CARD! 
Clue: Ken Jennings used these briefly displayed items to get ready to play "Jeopardy!"

A: flashcards
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Q: Category: HEY, J.J.! 
Clue: In 2001 his change of political affiliation tipped the balance of power in the Senate

A: jim jeffords
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Q: Category: IT'S ELEMENTAL 
Clue: Oxides of this silver-white metallic element are used in pigments to give some ceramics a vivid blue color

A:
cobalt
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