Economic efficiency A. is a market outcome in which the marginal benefit to consumers of the last unit produced is equal to its marginal cost of production. B. is a market outcome in which the sum of consumer surplus and producer surplus is at a maximum. C. is a market outcome in which every individual is better off than they would be at any other market outcome. D. both a and b. E. all of the above. Economists define economic efficiency in this way A. to help policymakers understand the negative consequences of price ceilings. B. to help policymakers understand the negative consequences of price floors. C. to illustrate the benefits of a competitive market equilibrium. D. to help policymakers understand the negative consequences of taxes. E. all of the above.