Which is NOT an advantage of emissions fees over standards?

A) Fees can give a firm the incentive to reduce emissions below the standard when new technology allows.
B) Fees can reduce the cost of attaining some goal level of emissions when firms all have the same abatement costs.
C) Fees can reduce the cost of attaining some goal level of emissions when firms have different abatement costs and different standards can be assigned to different firms.
D) Fees can reduce the cost of attaining some goal level of emissions when firms have different abatement costs and different standards cannot be assigned to different firms.
E) Fees may provide an incentive for a firm to investigate emissions-reduction technology that will reduce emissions below existing standards.

C