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: REALLY GRIMM FAIRY TALES 
Clue: To marry a princess, Hans had to pluck a feather from the tail of this beast that was part lion, part eagle

A: griffin
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Q: Category: TRANSPORTATION 
Clue: In the 19th century Gustavus Swift developed this type of railway car to preserve his packed meat

A: refrigerator car
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Q: Category: "G.G." 
Clue: This composer's "Porgy And Bess" is perhaps the most popular opera ever written by an American

A:
george gershwin
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