问题如下：
Tim is a fund manager in a wealth management firm. In a meeting with Wang, a derivatives strategist, Tim asks Wang to suggest a type of CDS contract to simultaneously fully hedge multiple fixed-income exposures.
According to the information above, which type of CDS should Wang recommend to Tim?
选项：
A.Single-name CDS
B.CDS index
C.Tranche CDS
解释：
B is correct.
考点：对CDS分类的理解
解析：
根据Tim的要求，同时对多个Exposure提供保护，那么应该购买CDS index.
请问tranche CDS是啥？
