The term structure of interest rates is upward sloping for all bond types. A certain AAA-rated callable 10-year corporate bond has been issued at a 6.15 percent promised yield. Which one of the following bonds probably has a lower promised yield?

A. A callable AAA-rated corporate bond with a 15-year maturity

B. A non-callable AAA-rated corporate convertible bond with a 10-year maturity

C. All of these choices are correct

D. A non-callable AAA-rated corporate bond with a five-year maturity

E. A similar quality municipal bond