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

A: dualism
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Q: Category: SICKNESS & HEALTH 
Clue: The initials HMO, which have stood for heart minute output, now also stand for this

A: health maintenance organization
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Q: Category: PSYCHOLOGY JARGON 
Clue: These 2 types of behavior, desiring pain & seeking to inflict it, are both named for novelists

A:
sadomasochism or sadism & masochism
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