从正态分布的总体中抽样,其样本均数([img=~/QImg/2013-10-14-10-46-38/image106.gif])和标准差(s)的关系是

A、s愈大,[img=~/QImg/2013-10-14-10-46-38/image106.gif]对各变量值的代表性愈好
B、s愈小,[img=~/QImg/2013-10-14-10-46-38/image106.gif]对各变量值的代表性愈好
C、s愈小,[img=~/QImg/2013-10-14-10-46-38/image106.gif]与总体均数的距离愈大
D、[img=~/QImg/2013-10-14-10-46-38/image106.gif]愈大,s愈大
E、[img=~/QImg/2013-10-14-10-46-38/image106.gif]愈大,s愈小