[Tex/LaTex] Change Multiple Choice Numbering in Exam Class

Question

I would like to change the numbering of the multiple choice from upper case letters to lower case. Here's my code

\documentclass[11pt,a4paper,answers,addpoints]{exam}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{fp}
\usepackage{multicol}


\correctchoiceemphasis{}

\begin{document}

\begin{questions}
    \question
     The valence electrons are: 
     \begin{multicols}{2}
        \begin{choices}
            \choice 
            Electrons in the first orbit.
            \correctchoice 
            Electrons in the outer orbit.
            \choice 
            Core electrons.
            \choice 
            Core electrons.         
        \end{choices}
    \end{multicols}
    %
    \question
     The band gap is: 
     \begin{multicols}{2}
        \begin{choices}
            \choice 
            Energy difference between 1st and 2nd electron energy bands.
            \choice 
            Energy difference between the core and valence bands.
            \choice 
            Energy difference between the valence and the conduction bands.
            \choice 
            Energy difference between the core and the conduction bands.        
        \end{choices}
    \end{multicols}
    %       
\end{questions}

\end{document}

I found a similar post but to change it to circled numbers, is there a way to do a similar thing

\renewcommand\choicelabel{\thechoice}
\renewcommand\choiceshook{
  \addtocounter{choice}{191} 
}
\renewcommand\thechoice{\ding{\arabic{choice}}}

Thanks!

Answer 1

You should use \renewcommand\choicelabel{\alph{choice}}.

\documentclass[11pt,a4paper,answers,addpoints]{exam}
\usepackage[utf8]{inputenc}
\usepackage{multicol}


\correctchoiceemphasis{}

\renewcommand\choicelabel{\alph{choice}}

\begin{document}

    \begin{questions}
        \question
        The valence electrons are: 
        \begin{multicols}{2}
            \begin{choices}
                \choice 
                Electrons in the first orbit.
                \correctchoice 
                Electrons in the outer orbit.
                \choice 
                Core electrons.
                \choice 
                Core electrons.         
            \end{choices}
        \end{multicols}
        %
        \question
        The band gap is: 
        \begin{multicols}{2}
            \begin{choices}
                \choice 
                Energy difference between 1st and 2nd electron energy bands.
                \choice 
                Energy difference between the core and valence bands.
                \choice 
                Energy difference between the valence and the conduction bands.
                \choice 
                Energy difference between the core and the conduction bands.        
            \end{choices}
        \end{multicols}
        %       
    \end{questions}

\end{document}

This code will appear as: