The Main Distinction Between a Forward and a Futures Contract

The main distinction between a forward and a futures contract is:

A) a forward contract has a final cash flow,while a futures contract has daily cash flows
B) a forward contract requires no collateral,while a futures contract requires traders to post margins
C) a forward trade is usually closed out early,while a futures trade usually ends with physical delivery
D) a forward trade requires cash settlement,while a futures trade does not require this
E) minor-they are the same contracts