Problem 2.6. (5 points) We are given the following European-call prices for options on the same underlying $50-strike $11 $55-strike $6 $60-strike $4 Assume that the continuously compounded interest rate is strictly positive. Which of the following portfolios asset: would exploit an arbitrage opportunity stemming from the above stock prices? (a) The call bull spread only (b) The call bear spread only. (c) Both the call bull and the call bear spread. (d) Neither the call bull or call bear spread, but there is an arbitrage opportunity (e) There is no apparent arbitrage opportunity