问题
单项选择题
One reason that criticism has been leveled at derivatives and derivatives markets is that:()
A. derivatives have too much default risk.
B. markets for derivatives seldom function efficiently like a stock exchange.
C. they are complex instruments and sometimes hard to understand.
答案
参考答案：C
解析：
The fact that derivative securities are sometimes complex and often hard for non-financial commentators to understand has led to criticism of derivatives and derivative markets.