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: SCIENCE FICTION 
Clue: A recent re-issue of this Sir Arthur Conan Doyle novel includes an introduction by Michael Crichton

A: the lost world
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Q: Category: THE CALENDAR 
Clue: Civilization that produced the first known calendar with 365 days

A: ancient egypt
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Q: Category: THE MIDDLE AGES 
Clue: Some say the Dark Ages began when Byzantine Emperor Justinian closed this city's school of philosophy in 529 A.D.

A:
athens
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