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: MARK ANTONYMS 
Clue: The traditional mark of someone who can't sign his name has this opposite in tic-tac-toe
o

Category: RED SOX IT TO ME 
Clue: On April 20, 1912 the first game at this new venue went 11 innings & ended with a Red Sox win
fenway park

Category: AUTHORS 
Clue: In 1997 he put his "Spenser" books on hold to introduce a new protagonist, Jesse Stone in "Night Passage"

robert parker