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: ON THE COAST 
Clue: A 19th c. "Committee of Vigilance" fought the crime that gave part of San Francisco this North Africa-inspired nickname

Answer: the barbary coast


Question: Category: THE KOREAN WAR 
Clue: In bitter battles of 1951, Pork Chop was a hill & Heartbreak was one of these

Answer: ridge


Question: Category: WYOMING 
Clue: The source of this main tributary of the Columbia River is located in Yellowstone National Park

Answer:
the snake river