How can I align the phrases on a exam document?

Question

I am trying to make a exam type class, and my output looks like this:

When it should look like these:

Besides, I cant make the math expressions bigger or look like the format I am using, how could I make both things happen? My code is:

\begin{document}
\begin{questions}
\question {\large Si $\large2n$ representa un número par y m un número impar, ¿Cuál de las siguientes opciones corresponde a un número par?}
\\
\begin{choices}
\choice $2n + m$
\\
\choice $2n - m$
\\
\choice $m - 2n + 2$
\\
\choice $10n + 3m$
\\
\choice $m - 1 + 2n$
\\
\end{choices}
\end{document}

Answer 1

If I understand your question right, maybe the package \relsize will help you. With the command \mathlarger in math mode, the output gets bigger.

\begin{document}
\begin{questions}
\question {\large Si $\large2n$ representa un número par y m un número impar, ¿Cuál de las siguientes opciones corresponde a un número par?}
\\
\begin{choices}
\choice $\mathlarger{2n + m}$
\\
\choice $\mathlarger{2n - m}$
\\
\choice $\mathlarger{m - 2n + 2}$
\\
\choice $\mathlarger{10n + 3m}$
\\
\choice $\mathlarger{m - 1 + 2n}$
\\
\end{choices}
\end{document}