In the given matrix \[\left[ {\begin{array}{*{20}{c}} 1&{ - 1}&2 \\ 0&1&0 \\ 1&2&1 \end{array}} \right],\]   one of the eigen values is 1. The eigen vectors corresponding to the eigen value 1 are

A. {α(4, 2, 1) |α ≠ 0, α \[ \in \] R}

B. {α(-4, 2, 1) |α ≠ 0, α \[ \in \] R}

C. {α(√2, 0, 1) |α ≠ 0, α \[ \in \] R}

D. {α(-√2, 0, 1) |α ≠ 0, α \[ \in \] R}

Answer: Option B