For a given good or service, the marginal social benefit ( MSB and the marginal social cost (MSC) curves are least accurately described by which of the following（）
A: Producer surplus is determined by price and the MSC curve and consumer surplus is determined by price and the MSB curve.
B: The efficient allocation of resources occurs where the difference between the MSB and MSC curves is maximized.
C: The market demand curve is the same as the MSB curve, and the market supply curve is the same as the MSC curve.