Refer to the above figure. Suppose the marginal benefit and the marginal cost curves of pollution abatement are normally shaped. Technological change that made it easier to produce in a “cleaner” fashion would cause

A) curve (4 ) to shift out, increasing the optimal amount of pollution abatement.
B) curve (3 ) to shift up, raising the marginal benefits and costs and reducing the amount of pollution abatement.
C) curve (2 ) to shift out, increasing the optimal amount of pollution abatement.
D) curve (1 ) to shift out, increasing the optimal amount of pollution abatement.