Which of the following statements is true?
a. money is a medium of exchange.
c. money serves as a store of value.
b. money is a unit of account.
d. all of the above

Answer;

A. Money is a medium of exchange.

Explanation;

Money actually serves several different key functions in our economy. It is a medium of exchange, a unit of account, and a store of value.

Medium of Exchange: When money is used to intermediate the exchange of goods and services, it is performing a function as a medium of exchange.Unit of Account: It is a standard numerical unit of measurement of market value of goods, services, and other transactions.Store of Value: To act as a store of value, money must be reliably saved, stored, and retrieved. It must be predictably usable as a medium of exchange when it is retrieved.

My answer is opptionc, just check with anyone else