问题如下：
6. In both of Mayer’s optimization scenarios, which of the following model inputs could be used without adjustment?
选项：
A.Expected returns
B.Correlation of returns
C.Standard deviations of returns
解释：
B is correct.
After- tax portfolio optimization requires adjusting each asset class’s expected return and risk for expected taxes. The correlation of returns is not affected by taxes and does not require an adjustment when performing after- tax portfolio optimization.
请问C为什么需要调整呢，谢谢
