问题如下图：
A项麻烦解释下，谢谢
选项：
A. 
B. 
C. 
解释：
NO.PZ2015121810000070 The range of risk exposures available in the futures market is more verse ththavailable in the ETF space. ETFs thhave the highest trang volumes in their asset class category are generally preferrefor tactictrang applications. C is correct. ETFs thhave the highest trang volumes in their asset class category are generally preferrefor tactictrang applications. 老师，B能在讲一下嘛？课件上没有找到相关的知识呢
NO.PZ2015121810000070 可以一下B和C吗？
The range of risk exposures available in the futures market is more verse ththavailable in the ETF space. ETFs thhave the highest trang volumes in their asset class category are generally preferrefor tactictrang applications. C is correct. ETFs thhave the highest trang volumes in their asset class category are generally preferrefor tactictrang applications. A为什么错，对比fixeincome,equity不是更活跃，流动性更强嘛
The range of risk exposures available in the futures market is more verse ththavailable in the ETF space. ETFs thhave the highest trang volumes in their asset class category are generally preferrefor tactictrang applications. C is correct. ETFs thhave the highest trang volumes in their asset class category are generally preferrefor tactictrang applications. 难道bonETF比Equity ETF更active吗
老师请问，为何FixeIncome会更加active一些
