When placing each of the digits $2,4,5,6,9$ in exactly one of the boxes of this [subtraction](https://artofproblemsolving.com/wiki/index.php/Subtraction) problem, what is the smallest [difference](https://artofproblemsolving.com/wiki/index.php/Difference) that is possible?
\[\begin{tabular}[t]{cccc}  & \boxed{} & \boxed{} & \boxed{} \\ - & & \boxed{} & \boxed{} \\ \hline \end{tabular}\]
$\text{(A)}\ 58 \qquad \text{(B)}\ 123 \qquad \text{(C)}\ 149 \qquad \text{(D)}\ 171 \qquad \text{(E)}\ 176$
When trying to [minimize](https://artofproblemsolving.com/wiki/index.php/Minimum) $a-b$, we minimize $a$ and [maximize](https://artofproblemsolving.com/wiki/index.php/Maximum) $b$.  Since in this problem, $a$ is three digit and $b$ is two digit, we set $a=245$ and $b=96$.  Their difference is $149\rightarrow \boxed{\text{C}}$.