The Bank of Canada Establishes a Rate at Which They

The Bank of Canada establishes a rate at which they will lend to commercial banks and a rate at which they will borrow from commercial banks.By doing so,

A) the Bank of Canada can ensure that the actual overnight interest rate will never fall below 2%.
B) the Bank of Canada can ensure that the commercial banks will not be earning excess profits.
C) the Bank of Canada can ensure that money demand remains at the level necessary for monetary equilibrium.
D) the Bank of Canada establishes a spread,into which all interest rates in the economy fall.
E) the Bank of Canada can ensure that the actual overnight interest rate will fall between these two interest rates.