Which of the Following Statements Best Describes Yield

Which of the following statements best describes yield?

A) A bond's current yield must always be either equal to its yield to maturity or between its yield to maturity and its coupon rate.
B) If a bond sells at par, then its current yield will be less than its yield to maturity.
C) If a bond sells for less than par, then its yield to maturity is less than its coupon rate.
D) A discount bond's price declines each year until it matures, when its value equals its par value.