# How to include graphics with width in the exam class?

I am trying to compose an exam with a figure as part of the question. However, I am having trouble using the standard \includegraphics command with pdflatex. I can not specify the arguments to \includegraphics in the square brackets. If I remove the square bracket (optional arguments), then it compiles without issue. I've tried wrapping it in the \fullwidth{} command to no avail.

Here is a minimal example:

\usepackage{graphics}
\begin{document}
\begin{questions}
\question[] True/False questions.
\begin{parts}
\part[2] True or False.\vspace*{1in}
An image:
\begin{figure}
\includegraphics[width=\textwidth]{file-which-exists}
\end{figure}
\end{parts}
\end{questions}

\end{document}`
-
A general comment: Using \linewidth instead of \textwidth might be more appropriate. The reason for this is that \textwidth may be fixed across your entire document, while \linewidth may vary, depending on the environment you're in. For example, in enumerate or itemize (typical for question-style documents like an examination), the \linewidth is smaller than \textwidth (due to the added indent). This leads to a better horizontal fit on the page. –  Werner Oct 1 '11 at 0:02