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.

Category: COLLEGES & UNIVERSITIES 
Clue: This New York univ. is named for the family whose company was the first to sell toothpaste in a tube
colgate university

Category: GEORGE WASHINGTON 
Clue: In 1798 George wrote to John Greenwood, a man in this profession, "I am...ready to pay what ever you may charge me"
dentist

Category: THE PULITZER PRIZE FOR DRAMA 
Clue: 1 of the 2 1-word plays, winners in 2001 & 2005, which both became movies; if you have one, you want the other

proof & doubt