b选项为什么不对呢

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%。