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.

Category: MONEY TALKS 
Clue: This phrase for cash set aside for trifles goes back to what was a luxury item for 14th century seamstresses
pin money

Category: THE NEW YORK TIMES ENTERTAINMENT 
Clue: "Oil!", a 1927 novel by this muckraker, was on the New York Times Best Seller List in 2008
upton sinclair

Category: PAPER 
Clue: The test named for this chemical paper has one decisive factor

litmus paper