$A=\left[\begin{array}{cc}1 & 2 \\-2 & 3\end{array}\right],$$B=\left[\begin{array}{cc}1 & 0 \\0 & -3\end{array}\right]$ হলে $\mathrm{A B}=\text { ? }$

$\left[\begin{array}{cc}1 & 6 \\-2 & -9\end{array}\right]$

$\left[\begin{array}{cc}1 & -6 \\-2 & -9\end{array}\right]$

$\left[\begin{array}{cc}1 & -2 \\-6 & -9\end{array}\right]$

$\left[\begin{array}{cc}1 & 6 \\2 & -9\end{array}\right]$