$\mathrm{A}=\left[\begin{array}{ll}1 & 2 \\3 & 4\end{array}\right], \mathrm{B}=\left[\begin{array}{ll}5 & 0 \\2 & 1\end{array}\right]$ হলে $\mathrm{AB}=\text { ? }$

$\left[\begin{array}{cc}9 & 2 \\23 & 4\end{array}\right]$

$\left[\begin{array}{ll}4 & 2 \\6 & 8\end{array}\right]$

$\left[\begin{array}{cc}5 & 0 \\10 & 5\end{array}\right]$

$\left[\begin{array}{ll}1 & 2 \\3 & 4\end{array}\right]$