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.

Category: PREPOSITIONAL PHRASES 
Clue: This Bob Seger song gained commercial popularity in Chevy truck ads
"like a rock"

Category: WHAT SHOULD I "DU"? 
Clue: A philosophical system that seeks to explain all phenomena in terms of 2 distinct principles
dualism

Category: "BOOT" CAMP 
Clue: It's a common name for a Wild West cemetery

boot hill