Refer to Figure 35

Refer to Figure 35.5.If S₁ represents the U.S.domestic supply of a good and S₂ represents supply in the United States under conditions of free trade, what does S₃ most likely represent?

A) U.S. supply under tariff-restricted trade.
B) U.S. supply under quota-restricted trade.
C) The result of a foreign country dumping this good on the U.S. market.
D) Production possibilities under conditions of free trade.