问题如下：
The data in the following table is obtained by analyst using historical information:
The Analyst also manages to observe that the spread between the five-year default-free nominal bond and the default-free real zero-coupon bond in Country C is 2.35%, which of the following statement is correct?
选项：
A.expected rate of inflation is less than 2.35%.
B.expected rate of inflation is larger than 2.35%.
C.expected rate of inflation is equal to 2.35%.
解释：
A is correct.
考点：Breakeven inflation rates (BEI)
解析：the difference between the default-free nominal bond and the default-free real zero-coupon bond is BEI.
BEI=expected inflation rate + uncertainty of inflation rate. 不确定性即是风险，对于风险就有风险补偿，这样的补偿通常认为是正的，所以uncertainty of inflation rate>0.
因此当BEI=2.35%时, 而uncertainty of inflation rate>0，那么expected rate if inflation 小于2.35%。
老师你好，请问为什么这里的default-free real zero-coupon bond 为什么不包含theta呢？
而在impact of inflation的内容里，ST bond是包含real rf + expect inflation的
请问该怎么区别和理解呢？谢谢老师
