If a country wants to keep its exchange rate from changing, it must give up some control

Question:

If a country wants to keep its from changing, it must give up some control over its money supply. Is this statement true, false, or uncertain? Explain your answer.

Exchange Rate
The value of one currency for the purpose of conversion to another. Exchange Rate means on any day, for purposes of determining the Dollar Equivalent of any currency other than Dollars, the rate at which such currency may be exchanged into Dollars...