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.

[EX Q]: Category: "F" 
Clue: One may be electric or alluvial; that's cool
[EX A]: a fan

[EX Q]: Category: IT'S NOT SO 
Clue: Though 4,500 miles long, it's not visible from space, as its materials are similar in color to the surrounding soil
[EX A]: the great wall of china

[EX Q]: Category: 4-LETTER WORDS 
Clue: To meditate upon something -- Terpsichore, for example
[EX A]:
muse