Saying "the marginal costs are greater than the marginal benefits" is the same as saying the average costs are greater than the average benefits. the total costs are greater than the average benefits. the benefits are greater than the costs. the additional costs are greater than the additional benefits. the costs minus the benefits equal the net costs.

With signals from no-claim bonuses and deductibles, a. the marginal cost curve for careful drivers lies to the left of the marginal cost curve for aggressive drivers b. auto insurance companies insure more aggressive drivers than careful drivers because aggressive drivers have a greater need for the insurance c. the market for car insurance has a separating equilibrium, and the market is efficient d. most drivers pay higher premiums than if the market had no signals