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: GEOLOGISTS 
Clue: In 1957 Sir Vivian Fuchs led the first crossing of this continent; it took 99 days

A: antarctica
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Q: Category: MATH TERMS 
Clue: The term surd refers to irrational numbers like this number's square root, 1.7320508...

A: 3
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Q: Category: OH, THAT MARIA! 
Clue: This diva seen here was renowned for her romance with Aristotle Onassis

A:
maria callas
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