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: OCEAN O' LOTION 
Clue: This principal constituent of oil of peppermint can be an ingredient in both cigarettes & lotions

A: menthol
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Q: Category: THE ELEMENTS 
Clue: Most fluorescent lights are filled with a combination of argon & this element, Kr

A: krypton
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Q: Category: JUST FOR THE "HALL" OF IT 
Clue: It's a false perception when no external stimulus exists

A:
hallucination
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