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: PATRIOTIC SONG TITLES 
Clue: "What so proudly we hailed at the twilight's last gleaming"

Answer: the "star-spangled banner"


Question: Category: ON THE GO 
Clue: John Ericsson, who built a steam locomotive in England in 1829, built this famous Civil War steam-powered ship

Answer: the monitor


Question: Category: NUTRITION 
Clue: This trace mineral, Se, may slow down the aging process by attacking free radicals in the body

Answer:
selenium