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: QUOTES 
Clue: 19th century philosopher & poet who advised "Hitch your wagon to a star"

A: ralph waldo emerson
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Q: Category: THE WRITE BROTHERS 
Clue: The younger brother of novelist Heinrich Mann, he wrote "Joseph and His Brothers"

A: thomas mann
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Q: Category: CASTLING 
Clue: No castle is complete without this deep trench that prevents access from the surrounding land

A:
a moat
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