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: RIVERS 
Clue: The mouth of this 2315-mile-long river lies in the Mississippi River 17 miles above St. Louis

A: the missouri
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Q: Category: THE 76th ACADEMY AWARDS 
Clue: He took home the little bald guy for the first time in 4 tries, winning Best Actor for "Mystic River"

A: sean penn
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Q: Category: COMPOUND WORDS 
Clue: April brings the National Safety Week for these places--uh-oh, that swing's looking rusty

A:
playgrounds
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