Refer to the Provided Supply and Demand Graph for a Product

Multiple Choice

Refer to the provided supply and demand graph for a product. In the graph, line S is the current supply of this product, while line S₁ is the optimal supply from the society's perspective. One solution to this externality problem is to

A) give consumers a subsidy of the amount FG per unit.
B) give producers a subsidy of the amount AB per unit.
C) tax producers by the amount DE per unit.
D) tax consumers by the amount EF per unit.