问题如下：
Which of the following statements regarding applications of ETFs in portfolio management is correct?
选项：
A.Equity ETFs tend to be more active than fixed-income ETFs.
The range of risk exposures available in the futures market is more diverse than that available in the ETF space.
ETFs that have the highest trading volumes in their asset class category are generally preferred for tactical trading applications.
解释：
C is correct. ETFs that have the highest trading volumes in their asset class category are generally preferred for tactical trading applications.
老师请问，为何Fixed Income会更加active一些
固定收益类型的ETF，因为底层资产的流动性差会影响其ETF的流动性、交易手续费、申赎和计税等情况。