Recall the Application About Reducing Pollution Generated from International Shipping

Recall the Application about reducing pollution generated from international shipping to answer the following question(s) .
-According to the Application,3% of global CO₂ emissions come from international shipping.What tool did the policy analysts use for comparing the cost of alternative reduction methods?

A) They computed the average marginal cost of each method.
B) They computed the marginal abatement cost of each method.
C) They computed the total marginal cost of each method.
D) The analysts were unable to compare the costs of alternative reduction methods.