/I> is specified).  If
one or more <I>option-value</I> pairs are specified, then the command
modifies the given widget option(s) to have the given value(s);  in
this case the command returns an empty string.
<I>Option</I> may have any of the values accepted by the <B>menubutton</B>
command.
<P></DL>
<H3><A NAME="M16">DEFAULT BINDINGS</A></H3>
Tk automatically creates class bindings for menubuttons that give them
the following default behavior:
<P>
<OL class="default bindings">
<LI value="1">
A menubutton ac