请解释AC选项

问题如下：

Which of the following statements describing a par curve is incorrect?

选项：

A.

A par curve is obtained from a spot curve.

B.

All bonds on a par curve are assumed to have different credit risk.

C.

A par curve is a sequence of yields-to-maturity such that each bond is priced at par value.

解释：

B is correct.

All bonds on a par curve are assumed to have similar, not different, credit risk. Par curves are obtained from spot curves and all bonds used to derive the par curve are assumed to have the same credit risk, as well as the same periodicity, currency, liquidity, tax status, and annual yields. A par curve is a sequence of yields-to-maturity such that each bond is priced at par value.

考点：par curve

解析：par rate 是一个人为设定的特殊债券，这个特殊债券的价格等于面值，因此收益率等于票面利率。由于这个设定的债券价格都等于面值，因此具有相同的货币、相同的流动性、相同的信用风险、相同的税务情况等等。故选项B说法不正确，当选。