What is an interest rate? A. a loan add-on B. a required bank fee C. a service provided by a retail store D. a special type of price.

An interest rate refers to the percentage rate charged for borrowing money or the return earned on an investment. Thus, the correct answer is not listed among the given options.

It has to be, look at it again please

I apologize for the confusion. Among the given options, the most accurate answer would be A. a loan add-on. An interest rate can be seen as a percentage charged on the principal amount borrowed, which is added to the loan amount and paid back to the lender along with the principal as part of the repayment.

so it's A.

Yes, that is correct. The correct answer is A. a loan add-on.