问题如下图：
选项：
A. 
B. 
C. 
解释：
老师您好，这道题的知识点是哪个？
to be sure, 题目中的pure-discount bond 指的是零息债券是吗？依稀记得何老师对于零息债券介绍过一个知识点，就是capital gain的部分可以摊销在各年影响税基，是吗？
有点模糊，求老师通俗、详细解答下，谢谢。
The increase in the bons value is treateinterest income. The increase in the bons value is treatea capitgain. B is correct. increase in a pure-scount bons value typically is treateinterest income to the bonolr tauthorities. In many jurisctions, tauthorities periocally tthese interest incomes ring the bons life even though the bonolrs not receive any payments until maturity.老师问下 A具体是啥意思
Capitgains 不是interest income 么，如何区分两者。
