设向量组 $\alpha_1, \boldsymbol{\alpha}_2, \boldsymbol{\alpha}_3$ 线性无关, 则下列向量组线性无关的是
A. $\alpha_1+\alpha_2, \alpha_2+\alpha_3, \alpha_3-\alpha_1$
B. $\alpha_1+\alpha_2, \alpha_2+\alpha_3, \alpha_1+\alpha_2+\alpha_3$
C. $\alpha_1+\alpha_2, \alpha_2+\alpha_3, \alpha_1+2 \alpha_2+\alpha_3$
D. $\alpha_1-\alpha_2, \alpha_2-\alpha_3, \alpha_3-\alpha_1$