(Figure: Market 2) Use the Graph to Answer the Question

(Figure: Market 2) Use the graph to answer the question.
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The graph shows the marginal social cost, demand, and supply curves in the cinnamon roll market. A corrective tax of _____ per unit will move the cinnamon roll market to the socially optimal output of _____ units.

A) $4; 4
B) $8; 4
C) $6; 6
D) $2; 6