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Let $a=(a_{ij})$ be an $n$-rowed square matrix and $I_{12}$ be the matrix obtained by interchanging the first and second rows of the $n$-rowed Identify matrix. Then $AI_{12}$ is such that its first

1. Row is the same as its second row
2. Row is the same as the second row of $A$
3. Column is the same as the second column of $A$
4. Row is all zero
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$C$ is the answer, in $AI12$ matrix will result into the same matrix as $A$ but first column will be exchanged with second column.
$A$ matrix:
$a$  $b$  $c$
$d$  $e$  $f$
$g$  $h$  $i$

$I12$ matrix
$0$ $1$ $0$
$1$ $0$ $0$
$0$ $0$ $1$

resulted matrix
$b$ $a$ $c$
$e$ $d$ $f$
$h$ $g$ $i$