Which of These Are Arguments That Support the Position That

Which of these are arguments that support the position that the efficient market hypothesis fails in actual application?
I.Arbitrage may involve too much risk to offset irrational behaviour
II.Investors may be irrational
III.Irrationalities are contervailing
IV.Irrationality may be related across investors

A) II only
B) I and II only
C) I,II,and IV only
D) II,III,and IV only
E) I,II,III,and IV