Which of the Following Statements Is Most Correct

Which of the following statements is most correct?

A) A firm with a sinking fund payment coming due would generally choose to buy back bonds in the open market, if the price of the bond exceeds the sinking fund call price.
B) Income bonds pay interest only when the amount of the interest is actually earned by the company. Thus, these securities cannot bankrupt a company and this makes them safer to investors than regular bonds.
C) One disadvantage of zero coupon bonds is that issuing firms cannot realize the tax savings from issuing debt until the bonds mature.
D) Other things held constant, callable bonds should have a lower yield to maturity than noncallable bonds.
E) All of the above statements are false.