These tables correspond to inputs and outputs. Which of these input and output tables could represent a function rule, and which ones could not? Explain or show your reasoning.
Table A:
Table B:
\begin{tabular}{|c|c|}
\hline input & output \\
\hline$-2$ & 4 \\
\hline$-1$ & 1 \\
\hline 0 & 0 \\
\hline 1 & 1 \\
\hline 2 & 4 \\
\hline
\end{tabular}
\begin{tabular}{|c|c|}
\hline input & output \\
\hline 4 & $-2$ \\
\hline 1 & $-1$ \\
\hline 0 & 0 \\
\hline 1 & 1 \\
\hline 4 & 2 \\
\hline
\end{tabular}
Table $C:$
Table D:
\begin{tabular}{|c|c|}
\hline input & output \\
\hline 1 & 0 \\
\hline 2 & 0 \\
\hline 3 & 0 \\
\hline
\end{tabular}
\begin{tabular}{|c|c|}
\hline input & output \\
\hline 0 & 1 \\
\hline 0 & 2 \\
\hline 0 & 3 \\
\hline
\end{tabular}