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.

[EX Q]: Category: EMPERORS 
Clue: After becoming emperor of Ethiopia in 1930, he gave the country its first written constitution
[EX A]: haile selassie

[EX Q]: Category: 20th CENTURY NOVELS 
Clue: Manfred de Spain appears in "The Town", "The Mansion" & "The Reivers" by this author
[EX A]: faulkner

[EX Q]: Category: EXPRESSIONS 
Clue: This positive expression used since the 1940s promotes a type of stove
[EX A]:
"now you\'re cooking with gas"