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.

Q: Category: GO WITH THE FLOW 
Clue: The Tigris flows into this gulf

A: the persian gulf
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Q: Category: C PLUS 
Clue: C plus a cry of pain equals this, a sofa

A: couch
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Q: Category: THE PRICE IS RIGHT 
Clue: This man's then record-setting 70th home run ball sold for more than $3 million; he's now retired

A:
mcgwire
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