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: ASTRONOMY 
Clue: A galactic cloud of dust & gas, its name comes from the Latin for "cloud"
[A]: nebula


[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


[Q]: Category: THUMB ENCHANTED EVENING 
Clue: Abraham Lincoln once had this diminutive Barnum star & his wife over to the White House
[A]:
tom thumb