4) an arbitrageur should a) buy the call sell the index and invest at r. b) sell the call sell the index and invest at r. c) sell everything and take a vacation d) sell everything but shelter at home. 4) an arbitrageur should a) buy the call sell the index and invest at r. b) sell the call sell the index and invest at r. c) sell everything and take a vacation d) sell everything but shelter at home