Consider a binomial world in which the current stock price of 75 can either go up by 10 percent or down by 8 percent. The risk-free rate is 4 percent. Assume a one-period world. An exercise price is 80.

What is the hedge ratio of the call?

a) 0.714

b) 0.571

c) 0.823

d) 0.185

e) none of the above