对于一组保额损失率数据，其均方差与其算术平均值之比为（）。

A.损毁率

B.赔付率

C.稳定系数

D.安全系数

All in all, the TV programmes were peaceful and entertaining,but the following programme contains scenes that may be ______ to some viewers.

A．satisfying

B．disturbing

C．interesting

D．positive