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: U.S. RIVERS 
Clue: The Falls of Saint Anthony stop this mighty river from being navigable north of St. Paul, Minnesota

A: the mississippi
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Q: Category: A TRIP ON THE "L" 
Clue: Big building on the back of the U.S. $5 bill

A: lincoln memorial
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Q: Category: MYTHOLOGY 
Clue: Castor, Pollux & Theseus accompanied Jason on his journey aboard this ship

A:
the argo
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