c

Test question analysis: A credit card is an electronic payment card with functions such as consumption, transfer settlement, cash deposits and withdrawals, and credit loans. In the process of using a credit card, the functions of currency are circulation Means and means of payment, ②④ are correct, ① The value scale refers to the function of currency to express and measure the value of all other commodities, ③ The means of storage refers to the currency being saved as a general representative of social wealth, so judge credit cards from their meanings It does not have the functions of value scale and storage means.