可以解释一下选B的原因吗？谢谢

问题如下：

Which bond from Exhibit 1 is most likely callable?

选项：

A.Bond A B.Bond B C.Bond C

解释：

Solution

B is correct. Bond B is most likely callable because of the difference between its option-adjusted spread (OAS) and its Z-spread. The Z-spread is the yield spread that must be added to each point of the implied spot yield curve in order for the present value of the bond’s cash flows to equal its market price. The OAS considers the value of optionality in a bond’s cash flows. The theoretical value of a callable bond is less than that for an otherwise equivalent non-callable bond because of the value of the call option (the issuer’s right to retire the bond prior to maturity) being sold by the investor. The OAS is the constant spread that when added to all the one-period forward rates makes the arbitrage-free value of the bond equal to its market price.

A is incorrect because Bond A is likely a non-callable bond because its Z-spread and OAS are equal.

C is incorrect because Bond C is likely a non-callable bond because its Z-spread and OAS are equal.