An investor purchased a $10,000, 5-year corporate note one year ago for $10,440. The note pays an annual coupon of $600. Over the past year, the notes's annual yield-to-maturity has dropped by 1%. What total return did the investor earn over the year?

A. 8.5%

B. 9.0%

C. 9.5%

Please show detailed explanation, thank you very much!