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.
Example: Category: WHO'S BUYING? 
Clue: YouTube, in 2006
Example solution: google
Example explanation: Google acquired, i.e. bought, YouTube in 2006 for $1.65 billion.

Problem: Category: EXPRESSIONS 
Clue: This positive expression used since the 1940s promotes a type of stove

Solution: "now you\'re cooking with gas"