4. Which of the following statements about sinking fund is NOT true?

a Sinking fund provision facilitates the orderly retirement of the bond issue.

b Sinking funds are designed to protect bondholders, but it can work to hurt the bondholders in some situations.

c A company would prefer to use sinking fund to buy back its bonds if interest rate is above the coupon rate.

d A company would use sinking fund for open market purchase of bond if interest rate is below coupon rate.