What is the difference between futures and forward contracts?

A) Futures give the buyer the option of buying or selling currency at the futures price, while forward contracts create and obligation to buy or sell currency at the forward price

B) Futures provide downside protection, while allowing for upside gains, whereas forward contracts allow for unlimited gains and losses

C) Cash flows on futures contracts occur daily, whereas forward contracts only have a single cash flow at contract expiration

D) Futures require the payment of an upfront premium which forward contract do not require