与矩阵 $A=\left(\begin{array}{ccc}1 & 0 & 0 \\ 0 & -1 & 2 \\ 0 & 2 & 2\end{array}\right)$ 合同的矩阵是（ ）。
A. $\left(\begin{array}{lll}1 & & \\ & -1 & \\ & & -1\end{array}\right)$
B. $\left(\begin{array}{lll}1 & & \\ & 1 & \\ & & -1\end{array}\right)$
C. $\left(\begin{array}{lll}1 & & \\ & -1 & \\ & & 0\end{array}\right)$
D. $\left(\begin{array}{lll}1 & & \\ & 1 & \\ & & 0\end{array}\right)$ ．