参考答案：B

解析：

If real GDP rises, more goods and services are bought and sold, and more money is needed to conduct these transactions. Increases in real GDP shift the money demand curve up. Decreases in real GDP shift it down so that less money is demanded at each level of interest rates. The increased use of credit cards and debit cards, the availability of interest bearing checking accounts, easier transfer of funds from savings to checking, the proliferation of ATMs, and internet banking and bill paying are all financial innovations that have affected the demand for money curve. Overall, financial innovation has reduced the demand for money below what it would have been if only the increase in real GDP was at work. The increased uses of credit cards and ATMs have likely been the most important innovations with respect to the demand for money.