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: SUCH GOOD CHEMISTRY 
Clue: A U.S. nuclear weapon using this element, Co, has been termed a doomsday device, as it would wipe out life on Earth

A: cobalt
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Q: Category: LITERATURE 
Clue: George Du Maurier introduced this evil hypnotist in his 1894 novel "Trilby"

A: svengali
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Q: Category: BUMPER STICKER HUMOR 
Clue: "When" this food "gets its picture taken, what does it say?"

A:
cheese
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