问题如下：
Mowery informs Compton that DFC has a single $500 million liability due in nine years, and she wants SD&R to construct a bond portfolio that earns a rate of return sufficient to pay off the obligation. Mowery expresses concern about the risks associated with an immunization strategy for this obligation. In response, Compton makes the following statements about liability-driven investing:
Statement 1：Although the amount and date of SD&R’s liability is known with certainty, measurement errors associated with key parameters relative to interest rate changes may adversely affect the bond portfolios.
Statement 2：A cash flow matching strategy will mitigate the risk from non-parallel shifts in the yield curve.
Which of Compton’s statements about liability-driven investing is (are) correct?
选项：
A.Statement 1 only.
Statement 2 only
Both Statement 1 and Statement 2
解释：
C is correct.
Compton is correct that measurement error can arise even in immunization strategies for Type 1 cash flows, which have set amounts and set dates. Also, a parallel shift in yield curves is a sufficient but not a necessary condition to achieve the desired outcome. Non-parallel shifts as well as twists in the yield curve can change the cash flow yield on the immunizing portfolio; however, minimizing the dispersion of cash flows in the asset portfolio mitigates this risk. As a result, both statements are correct.
Although the amount and date of SD&R’s liability is known with certainty, measurement errors associated with key parameters relative to interest rate changes may adversely affect the bond portfolios.
请教下老师，请问statement 1 针对题干来说应该是错的吧，题目中提到是single liabilty，那么我通过Mac duration相同的零息债券match就完全避免model risk了，不会因为interest rate的变化而影响其match的效果。老师，我的理解是否正确，多谢！
