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.
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Question: Category: PRESIDENTIAL FIRSTS 
Clue: 1st president to refuse a 3rd term

Answer: george washington


Question: Category: SPORTS 
Clue: Football's imaginary plane which neither team may cross until the ball is snapped

Answer: the line of scrimmage


Question: Category: PIRATE MOVIES 
Clue: Silent screen swashbuckler; his film "The Black Pirate" has been called "a definitive pirate movie"

Answer:
douglas fairbanks, sr.