Use the Figure Below to Answer the Following Question(s)

Use the figure below to answer the following question(s) . Figure 18-2
In Figure 18-2, which of the following would cause the American demand for foreign exchange (pounds) to shift from D₁ to D₂?

A) an increase in the U.S. real interest rate
B) higher inflation in Britain than in the United States
C) higher income growth in Britain than in the United States
D) an increased level of vacation travel to Britain by Americans