In a Graph Showing the Market Supply and Demand for British

In a graph showing the market supply and demand for British pounds in terms of U.S. dollars, the supply-of-pounds curve is upsloping because:

A) Fewer British pounds can be purchased per dollar if U.S. dollars become more expensive
B) Fewer U.S. dollars can be purchased per pound if the British pounds become less expensive
C) The British will purchase more U.S. goods or services when the dollar price of pounds rises
D) The British will purchase more U.S. goods or services when the dollar price of pounds falls