Answer:
b. Store of value, unit of account, medium of exchange
Step-by-step explanation:
Money's function as a store of value is when it retains its intrinsic value for a considerable time and does not perish.
The function as unit of account is when commodities can be associated with a certain value in terms of money.
Medium of exchange is when money is generally and readily accepted by any and all economic agents in return for goods and services.
The correct order that explains these functions is
store of value, unit of account, medium of exchange
Hope that helps.