Assume that the reserve requirement is 20 percent, but banks voluntarily keep some excess reserves. A $1 million increase in new reserves will result in a) an increase in the money supply of $5 million. b) an increase in the money supply of less than $5 million. c) a decrease in the money supply of $1 million. d) a decrease in the money supply of $5 million. e) a decrease in the money supply of more than $5 million.