设 (alpha )_(1)=((0,0,{sigma )_(1))}^T , (alpha )_(2)=((0,1,{c)_(2))}^T , (alpha )_(3)=((1,-1,{c)_(3))}^r , _(4)=-|||-((-1,1,{c)_(4))}^T, 其中c1,c2,c3,c4为任意常数,则下列向量组线性相关的为-|||-()-|||-(a)α1,α2,α 3-|||-(b)α1,α2,α4-|||-(c)α1,α3,α4-|||-(d) α2,α3,α 4