LyX 中的幻灯片模板为包 graphicx 生成选项冲突

Question

slides即使是一个非常简单的例子（即带有 *.pdf 图的单张幻灯片），LyX 中的模板也会产生 错误

下面提供的源代码会产生此错误：

！LaTeX 错误：包 graphicx 的选项冲突。

描述如下：

软件包 graphicx 已使用以下选项加载：[] 现已尝试使用以下选项加载 [dvips] 将全局选项：,dvips 添加到您的 \documentclass 声明中可能会修复此问题。尝试输入以继续。

我是不是错过了什么简单的事情？有没有可以在 LyX GUI 中实施的解决方案？

% Preview source code
%% LyX 2.1.1 created this file.  For more info, see http://www.lyx.org/.
%% Do not edit unless you really know what you are doing.
\documentclass[landscape,english]{slides}
\usepackage{fontspec}
\setmainfont[Mapping=tex-text]{Linux Biolinum}
\setsansfont[Mapping=tex-text]{Linux Biolinum}
\setcounter{secnumdepth}{1}
\setcounter{tocdepth}{1}
\usepackage[dvips]{graphicx}

\makeatletter

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% LyX specific LaTeX commands.
\pdfpageheight\paperheight
\pdfpagewidth\paperwidth


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Textclass specific LaTeX commands.
\newcounter{slidetype}
\setcounter{slidetype}{0}
\newif\ifLyXsNoCenter
\LyXsNoCenterfalse
\newcommand{\noslidecentering}{
   \LyXsNoCentertrue%
}
\newcommand{\slidecentering}{
   \LyXsNoCenterfalse%
}
\newcommand{\lyxendslide}[1]{
   \ifLyXsNoCenter%
        \vfill%
   \fi%
   \ifcase \value{slidetype}%
        \or % no action for 0
        \end{slide} \or%
        \end{overlay} \or%
        \end{note}%
   \fi%
   \setcounter{slidetype}{0}
      \visible
}
\AtEndDocument{\lyxendslide{.}}
\newcommand{\lyxnewslide}[1]{
 \lyxendslide{.}
 \setcounter{slidetype}{1}
 \begin{slide}
}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% User specified LaTeX commands.
% Uncomment to print out only slides and overlays
%
%\onlyslides{\slides}

% Uncomment to print out only notes
%
%\onlynotes{\notes}

\makeatother

\usepackage{xunicode}
\usepackage{polyglossia}
\setdefaultlanguage{english}
\begin{document}

\lyxnewslide{}

Test slide.

\includegraphics[width=5cm,height=5cm]{../../../../plot}
\end{document}