15. How would the following influence the growth rates of the M1 and M2 money supply figures over time?

a. an increase in the quantity of U.S. currency held overseas

b. a shift of funds from interest-earning checking deposits to money market mutual funds

c. a reduction in the holdings of currency by the general public because debit cards have become more popular and widely accepted

d. the shift of funds from money market mutual funds into stock and bond mutual funds because the fees to invest in the latter have declined