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: THE ARMED SERVICES 
Clue: In September 1997 this branch of the U.S. Armed Services celebrated its 50th anniversary

Answer: u.s. air force


Question: Category: BIBLICAL AKA 
Clue: This second king of Israel was "the sweet singer of Israel"

Answer: king david


Question: Category: U.S. COLLEGES 
Clue: Its original home was built in 1829 as an arsenal to defend against slave insurrections

Answer:
the citadel