NO.PZ2017092702000002
问题如下：
Which of the following risk premiums is most relevant in explaining the difference in yields between 30-year bonds issued by the US Treasury and 30-year bonds issued by a small private issuer?
选项：
A.Inflation
B.Maturity
C.Liquidity
解释：
C is correct.
US Treasury bonds are highly liquid, whereas the bonds of small issuers trade infrequently and the interest rate includes a liquidity premium. This liquidity premium reflects the relatively high costs (including the impact on price) of selling a position.
美国国债具有高流动性，而小型的债券交易很少。而利率包含流动性溢价。 这种流动性溢价会反映出相对较高的成本（包括对价格的影响）。
能理解答案解析，但是考虑不好为什么会是流动性，觉得30年会有违约风险。小公司会不稳定
