Which of the following is/are true? I. The basic relationship in bond valuation is for a given percentage change in required rate of return, the longer the time to maturity, the smaller the change in bond value. II. The higher the investor's required rate of return on a bond, the lower will be the value of the bond to the investor. III. Bond prices of longer term bonds are more sensitive to changes in required rates of return than short-term bonds.

I, and II only I, and III only II and III only III only I only II only