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: JEWELRY 
Clue: An engraved gem with a design that projects from the surface, it can be carved from onyx, agate or sardonyx

A: a cameo
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Q: Category: IT'S NOT SO 
Clue: Though 4,500 miles long, it's not visible from space, as its materials are similar in color to the surrounding soil

A: the great wall of china
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Q: Category: POTPOURRI 
Clue: This 5th Ave. museum sells pins representing its unofficial mascot, William the Hippo

A:
the metropolitan museum of art
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