Figure 30-1 -Refer to Figure 30-1. Which of the Following Would Cause

Figure 30-1
-Refer to Figure 30-1. Which of the following would cause the change depicted in the figure above?

A) U.S. productivity falls relative to European productivity.
B) Americans increase their preferences for goods produced in the EU relative to American goods.
C) The United States imposes a quota on wine from the European Union.
D) The price level of goods produced in the EU decreases relative to the price level of goods produced in the United States.