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: HISTORIC BOOKS
Clue: It was written in 1924 in the fortress of Landsberg am Lech

Answer: mein kampf by adolf hitler

Question: Category: REPUBLICANS
Clue: 2 of the 3 Republicans elected vice president twice

Answer: spiro agnew, george bush & richard nixon

Question: Category: PRESIDENTS
Clue: This consonant begins the last names of five presidents, more than any other letter

Answer:
h