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: THE HISTORY OF APRIL 9th 
Clue: 1959: NASA publicly introduces Messrs. Glenn, Shepard & the rest of this program's 7 astronauts

A: mercury
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Q: Category: SPACE MISSIONS 
Clue: The New Horizons mission was launched to explore this planet before it was downgraded to a dwarf

A: pluto
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Q: Category: BONE UP FOR THE TEST 
Clue: "U" know it's the inner of 2 bones in the forearm when viewed with the palm facing forward

A:
the ulna
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