With regard to futures contracts, margin is:

	a.	A good faith deposit made at the time of the contract is bought or sold.
	b.	The maximum percentage that the price of the contract can change before it is marked-to-market.
	c.	The maximum percentage that the price of the underlying asset can change before it is marked-to-market.
	d.	The amount of the money borrowed from the broker to buy a contract.