It should be

@M North,South,Central

>Hi
>I'm trying to implement a multiple choice field in Fox 2.6 for DOS.
>I've got an old language reference here that says something about using the function code M.
>I'm working with the screen designer and I can't get the syntax right.
>I've been trying stuff (in the format box of the field) like:
>
>M North, South, Central
>
>or
>
>Function M North, South, Central
>
>Does anyone know what the proper syntax is for this function code and whether I'm putting the code in the right place or not.
>
>
>Phil