设 $\boldsymbol{A}$ 是三阶实对称矩阵，特征值是 $0,1,2$ ，若 $\boldsymbol{B}=\boldsymbol{A}^3-3 \boldsymbol{A}^2+2 \boldsymbol{E}$ ，则与 $\boldsymbol{B}$ 相似的矩阵是
$\text{A.}$ $\left[\begin{array}{lll}1 & & \\ & 3 & \\ & & -1\end{array}\right]$ ．
$\text{B.}$ $\left[\begin{array}{lll}2 & & \\ & 0 & \\ & & -2\end{array}\right]$ ．
$\text{C.}$ $\left[\begin{array}{lll}0 & & \\ & 1 & \\ & & 2\end{array}\right]$ ．
$\text{D.}$ $\left[\begin{array}{lll}2 & & \\ & 2 & \\ & & 6\end{array}\right]$ ．
$\text{E.}$
$\text{F.}$