Suppose That the United States Fixes the Dollar-Pound Exchange Rate

Suppose that the United States fixes the dollar-pound exchange rate. In the process of maintaining the fixed exchange rate, the U.S. central bank regularly finds itself in a position of having to increase its reserves of pounds. Based on this, we could conclude that

A) the fixed dollar-pound exchange rate is consistently below the equilibrium exchange rate that would be produced by a private foreign exchange market.
B) the fixed dollar-pound exchange rate consistently exceeds the equilibrium exchange rate that would be produced by a private foreign exchange market.
C) the fixed dollar-pound exchange rate is a good approximation of the exchange rate that would be produced by a private foreign exchange market.
D) the U.S. central bank is regularly having to reduce the domestic money supply.