In saying that the present system of floating exchange rates is managed we mean that: A) countries which allow their exchange rate to move freely will lose their borrowing privileges with the IMF. B) the value of any IMF member's currency can only vary 2 percent from its par value. C) IMF officials determine exchange rates on a day-to-day basis. D) the central banks of several countries sometimes buy and sell foreign exchange to alter undesirable trends in exchange rates.