问题如下：
A sovereign bond has a maturity of 15 years. The bond is best described as a:
选项：
A. perpetual bond.
B. pure discount bond.
C. capital market security
解释：
C is correct.
A capital market security has an original maturity longer than one year.
A is incorrect because a perpetual bond does not have a stated maturity date. Thus, the sovereign bond, which has a
maturity of 15 years, cannot be a perpetual bond. B is incorrect because a pure discount bond is a bond issued at a discount to par value and redeemed at par. Some sovereign bonds (e.g., Treasury bills) are pure discount bonds, but others are not.
请问B什么意思？学完好混乱
