The Safe Drinking Water Act required the US EPA to establish action standards for lead in drinking water. The agency considered three options (labeled A, B, and C below) using Cost-Benefit Analysis techniques. Total Benefits and Costs for these three options are in the table below in millions of 1988 dollars. Option C is the least stringent policy, and Option A the most stringent.

	Option
	A	B	C
Total Benefits	68,957	63,757	24,325
Total Costs	6,272	4,156	3,655
Benefit/Cost Ratio	11.0	15.3	6.7
Marginal Benefit (MB)	68957-63757 = 5200	68957-63757 = 5200
Marginal Cost (MC)
MB to MC Ratio
Net Benefits

A. Fill in the rest of the table. To do this, note that the policies build on each other Option B includes option C, and option A includes both B and C (and something more).

B. Which option is the most efficient choice?