Suppose that the par exchange rate was four US dollars per one British pound and the equilibrium exchange rate was two US dollars per one British pound. To defend the par exchange rate under the Bretton Woods System, ___________.

a.theBankofEnglandmust buyBritishpounds andsell USdollars toreducetheexcessdemand forBritishpounds

b.the Bank of England must buy British pounds and sell US dollars to reduce the excess supply of British pounds

c.theBankofEnglandmust sellBritishpounds andbuy USdollars to reduce the excess supply of British pounds

d.theBankofEnglandmust sellBritishpounds andbuy USdollars to reduce the excess demand for British pounds