TASK DEFINITION: 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.
PROBLEM: Category: WOMEN WRITERS 
Clue: Mary Chesnut's take on this U.S. war was part of a Ken Burns TV documentary

SOLUTION: the civil war

PROBLEM: Category: ANCIENT GREEKS 
Clue: This actor of the 6th century B.C. is credited with introducing the use of masks on stage

SOLUTION: thespis

PROBLEM: Category: FILL IN THE _____ 
Clue: Something hard to find resembles "a needle in a _____"

SOLUTION:
haystack