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: CLASSICAL MYTHOLOGY 
Clue: Achilles died after one of these weapons wounded him in the heel

A: an arrow
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Q: Category: "R"ITERS 
Clue: This author of the hitchhiking novel "Even Cowgirls Get the Blues" once hitchhiked across the U.S.

A: tom robbins
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Q: Category: GREEN ACRES 
Clue: The heart of Argentina's agricultural region is these grassy plains covering 300,000 square miles

A:
the pampas
****