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 consistency, answers should be in all lower cased letters.
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Question: Category: SYNONYMS 
Clue: This book of the Bible is a synonym of departure

Answer: exodus


Question: Category: LESSER-KNOWN AMERICANS 
Clue: A. Philip Randolph, who first proposed a march on this city in 1941, also helped organize the one in 1963

Answer: washington, d.c.


Question: Category: DIAMONDS ARE FOREVER 
Clue: Under intense heat & in the presence of oxygen, a diamond will burn &  form this gas

Answer:
carbon dioxide