Question

why do some accounts, like saving accounts at your local bank, earn interest?
○ because of inflation
○ because the bank pays you for the use of your money.
○ because you deposit money, adding to your principal each month
○ because those accounts always have great interest rates

Explanation:

Banks use the funds deposited in savings accounts to lend to other customers. They pay interest to account holders as compensation for allowing the bank to use their money. Inflation does not cause interest earnings, adding to principal is the result of interest, not the reason, and not all these accounts have great rates.

Answer:

Because the bank pays you for the use of your money.