设X_1, X_2, ..., X_(3n)是取自正态总体N(0, sigma^2)的简单随机样本，记[ T = c ((X_1 + X_3 + ... + X_(2n-1))^2)/((X_2 + X_4 + ... + X_(2n))^2 + (X_{2n+1) + X_(2n+2) + ... + X_(3n))^2} 其中c为非零常数，则当T服从自由度为(1,2)的F分布时c的值为A. 1B. 2C. 0.5D. 3

设$X_1, X_2, \cdots, X_{3n}$是取自正态总体$N(0, \sigma^2)$的简单随机样本，记\[ T = c \frac{(X_1 + X_3 + \cdots + X_{2n-1})^2}{(X_2 + X_4 + \cdots + X_{2n})^2 + (X_{2n+1} + X_{2n+2} + \cdots + X_{3n})^2} $其中$c$为非零常数，则当$T$服从自由度为$(1,2)$的$F$分布时$c$的值为

A. 1

B. 2

C. 0.5

D. 3