设(X1,X2,···,Nn)是来自正态总体N (μ,σ^2)的-|||-简单随机样本,X是样本均值,记-|||-({S)_(1)}^2=dfrac (1)(n-1)(sum )_(i=1)^n(({X)_(i)-overline (X))}^2 ,-|||-S2^2= ∑n (Xi-x)^2,-|||-({S)_(3)}^2=dfrac (1)(n-1)(sum )_(i=1)^n(({X)_(i)-mu )}^2-|||-,则下列说法不正确的是 () .-|||-(A) dfrac (n{{S)_(2)}^2}({sigma )^2}sim (x)^2(n-1) ;-|||-(B) dfrac ((n-1){{S)_(3)}^2}({sigma )^2}sim (chi )^2(n).-|||-(C) dfrac ((n-1){{S)_(3)}^2}({sigma )^2}sim (x)^2(n-1) =-|||-(D) dfrac ((n-1){{S)_(1)}^2}({sigma )^2}sim (x)^2(n-1)