问题如下：
Which of the following may have a lowest recovery rate in the event of liquidation?
选项：
A. Senior subordinated.
B. Senior unsecured.
C. Senior secured.
解释：
A is correct.
Senior subordinated debt ranks lower than the senior unsecured and senior secured debt, accordingly it has the lowest priority of payment and the lowest recovery rate.
可以解释一下吗。特别是recovery rate
