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: 3-LETTER WORDS 
Clue: To udderly intimidate someone

Answer: cow


Question: Category: SEX CHANGES 
Clue: Don't let the pearls fool you, these lady bivalves can change into males when it suits them

Answer: oysters


Question: Category: MAGAZINES 
Clue: It was primarily a fiction magazine until Helen Gurley Brown became editor in 1965

Answer:
cosmopolitan