Does the market system result in productive efficiency? in the long run, perfect competition

a. does not result in productive efficiency because barriers to entry result in firms making a profit.

b. results in productive efficiency because firms enter and exit until they break even where price equals minimum average cost.

c. does not result in productive efficiency because price-taking firms produce where price equals marginal cost.

d. results in productive efficiency because every good or service is produced up to the point where the last unit provides a marginal benefit to consumers equal to the marginal cost of producing it.

e. results in productive efficiency because production represents consumer preferences