The September T-bond futures contract is currently selling at 111-05 and September call option on T-bond futures for a strike price of 115-00 is currently quoting at 2-24. If an investor purchases one contract of the call option at the current market price and if the T-bond futures contract settles at 118-05 on the expiration day, what will be the net gain/loss for the investor?

A. $781.25

B. $281.25

C. -$359.38

D. $791.25

E. $566.25

The correct answer is A, I need to know how to get it??