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: AMERICAN EXPLORERS 
Clue: After being led there by a local, Hiram Bingham claimed he "discovered" this lost Incan city in Peru

A: machu picchu
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Q: Category: BRAIN STRAIN 
Clue: Appropriately, this stadium has hosted the NFL Super Bowl more than any other

A: louisiana superdome
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Q: Category: YOU NEED THERAPY 
Clue: In the hyperbaric type of this "therapy", the patient inhales the pure gas in a large chamber

A:
oxygen
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