Answer:
B) Is an agreement to buy or sell a specified amount of an asset at a predetermined price on the expiration date of the contract.
Step-by-step explanation:
A futures contract is when the agents agree a price for a specific asset. This asset is then bought and delivered in the future at the agreed upon price. This is a legally binding contract and obligates the agents to honor their part of the contract.
Therefore, in the light of above definition only option B stands out as the right answer.
Hope that helps.