Darcy has a savings account at a local bank. That same bank is advertising its best financing deals to the best credit$-$qualified borrowers: auto loans at $6\mathrm{.}5\%$ APR, home loans at $4\mathrm{.}2\%$ APR, and credit card purchase balances at $9\mathrm{.}9\%$ APR. Which of the following statements must be true?

Select answer from the options below

The interest rate that Darcy earns on her savings account is $9\mathrm{.}9\%.$

The interest rate that Darcy earns on her savings account is $6\mathrm{.}5\%.$

The interest rate that Darcy earns on her savings account is greater than $9\mathrm{.}9\%.$

The interest rate that Darcy earns on her savings account is lower than $4\mathrm{.}2\%.$