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: SAME FIRST & LAST LETTER 
Clue: An invisible emanation, or an intangible quality

A: aura
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Q: Category: MR. BODY 
Clue: Fed by the hepatic portal veins, it weighs about a pound more in men than in women

A: liver
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Q: Category: OF THE CHILDREN 
Clue: At the park the full bucket type of this is for 2- & 3-year-olds; kids who are 4 & 5 graduate to the half bucket

A:
a swing
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