Consider three bonds that have the same yield to maturity and maturity. The bond with the greatest reinvestment risk is most likely the one selling at:
C is correct because yield to maturity is based on the assumption a bond is held to maturity, does not default, and has its coupon payments reinvested at the yield to maturity. The bond selling at a premium has the highest coupon rate and is expected to earn the most reinvestment income from reinvesting those coupon payments at the yield to maturity. If the reinvestment rate falls, this bond will suffer the greatest loss.