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: DECEMBER 1st 
Clue: 1959: 12 countries including the U.S. & the U.S.S.R. sign a treaty to keep this continent a scientific preserve

A: antarctica
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Q: Category: A NOSE FOR GNUS 
Clue: A main predator of the adult gnu, it has a mane, too

A: lion
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Q: Category: ESPAÑOL 
Clue: In Spanish, oro is gold & plata is this metal

A:
silver
****