Excess Reserves Held by Banks as Hedges Against Seeing Their

Excess reserves held by banks as hedges against seeing their reserves fall below the 10 percent requirement

A) are generally quite small since no interest is earned on them.
B) tend to be largest when interest rates are high, since fewer people borrow money.
C) are generally about half of required reserves, so that banks can cover unexpected withdrawals.
D) have always been greater than zero because of penalties assessed by the Fed if total reserves fall below the reserve requirement.
E) none of the above.