A newly entered-into long forward contract on an asset and a long position in an European put option on the asset with the same maturity as the forward contract and a strike price that is equal to the forward price of the asset at the time the portfolio is set up.

(a) Show that the European put option has the same value as an European call option with the same strike price and maturity.

(b) Discuss why margins are required when options are sold. (need answer for this question)