答案
D
解析
】由题设, 将 $A$ 的第 1 列与第 2 列交换, 即
$$
A E_{12}=A\left[\begin{array}{lll}
0 & 1 & 0 \\
1 & 0 & 0 \\
0 & 0 & 1
\end{array}\right]=B,
$$
将 $B$ 的第 2 列加到第 3 列, 即
$$
B\left[\begin{array}{lll}
1 & 0 & 0 \\
0 & 1 & 1 \\
0 & 0 & 1
\end{array}\right]=A\left[\begin{array}{lll}
0 & 1 & 0 \\
1 & 0 & 0 \\
0 & 0 & 1
\end{array}\right]\left[\begin{array}{lll}
1 & 0 & 0 \\
0 & 1 & 1 \\
0 & 0 & 1
\end{array}\right]=A\left[\begin{array}{lll}
0 & 1 & 1 \\
1 & 0 & 0 \\
0 & 0 & 1
\end{array}\right]=A Q
$$
故 $Q=\left[\begin{array}{lll}0 & 1 & 1 \\ 1 & 0 & 0 \\ 0 & 0 & 1\end{array}\right]$, 应选(D).