Shares in a plc are currently trading at 500 each. A call option on one share of a plc with a strike price of X that expires in one year costs 68. A put option on one share of a plc with a strike price of X that expires in one year costs 18. The risk-free interest rate is 4% p.a. Based on the (discrete time) put-call parity, which of the following is closest to the strike price X?

A 568

B 518

C 468

D 450

E 428