问题如下：
Which of the following descriptions regarding collateralized mortgage obligations (CMOs) is most accurate?
选项：
A.CMO can change the prepayment risk.
B.CMO has a unique structure.
C.CMO broadens the appeal of mortgage-backed products.
解释：
C is correct.
The creation of CMO cannot eliminate or change the prepayment risk, but can only distribute the various forms of this risk among different bond classes. CMOs have a wide range of structures. CMO meets the assets/liability needs of institutional investors, thereby boardening the appeal of the mortgage-backed products.
a为什么不对，改变结构也是change啊，并没有说消除prepayment risk
