Write the Argument in Symbols; Then Decide Whether the Argument $\mathrm { A }$

Write the argument in symbols; then decide whether the argument is valid by using the common forms of valid arguments and fallacies.
You ate what was in your lunchbox or you didn't get an A.
You didn't get an $\mathrm { A }$
$\therefore$ You didn't eat what was in your lunchbox

A) Invalid
$\begin{array}{l}p \rightarrow q \\\sim q\\\hline\therefore\sim p\end{array}$

B) Valid
$\begin{array}{l}p \rightarrow q \\\sim q\\\hline\therefore \sim p\end{array}$

C) Valid
$\begin{array}{l}p \rightarrow q \\\sim q\\\hline\therefore\sim p\end{array}$

D) Invalid
$\begin{array}{l}p \rightarrow q \\\sim q\\\hline\therefore\sim p\end{array}$