--- Be sure to get there on time, ______ you?

--- Of course, we ______.

A．will; will

B．are; shall

C．will; do

D．can; must

某股票标准差为0.8，其与市场组合的相关系数为0.6，市场组合标准差为0.4。该股票的收益与市场组合收益之间的协方差和该股票的9系数分别为( )。

A．0.192和1.2

B．0.192和2.1

C．0.32和1.2

D．0.32和2.1