NO.PZ2019011002000026
问题如下：
Li is a credit analyst in a wealth management firm.
Li believes the US economy is improving, and the economy will strengthen in the short-term. Thus, the credit spread curve will become more steepening with short-term credit spread decreasing. Li wants to capitalize his view of the steepening US credit curve.
According to the information above, the curve trade that Li could use it:
选项：
A.Short short-term CDX and long long-term CDX
B.long short-term CDX and Short long-term CDX
C.Long short-term CDX and long long-term CDX
解释：
B is correct
考点：CDS的应用。
解析：
因为预测Credit curve会变得更加Steepening，短期的Credit spread会下降，因此可以卖出短期的CDS protection来赚取保费，同时可以买入长期的Protection。而卖出短期Protection，相当于主动承担了短期的Credit risk，因此是Long short-term CDS；而买入长期的Protection，相当于转移出去了长期的Credit risk，因此是Short long-term CDS。因此B正确。
CDX 是指 Index CDS吧？
前面答案中：
“CDS的标的物可以看成是Credit risk，所以Long CDS就是Long credit risk，主动承担信用风险；Short CDS就是short credit risk，转移信用风险。”
CDS 的直观理解到底是 protection 还是 credit risk？
答案解释里面 是把CDX 等同于Credit Risk（风险）的概念了吧？
我这样理解：
从Li的视角看
Curve steepen--->短期风险低---->主动买入风险=Long 短期-CDX=Sell protection（对手方视角）
--->长期风险高---->卖出风险=Short 长期CDX =Buy Proction（对水方视角）
