Runtime Error


I've been able to create the control on the page just fine. I can run the app and click on the dropdowncheckbox and click on a single item and I get the following error:

Unhandled exception at line 1, column 2139 in http://localhost:60375/bundles/MsAjaxJs?v=c42ygB2U07n37m_Sfa8ZbLGVu4Rr2gsBo7MvUEnJeZ81
0x800a01b6 - JavaScript runtime error: Object doesn't support property or method 'apply'

I'm in Visual Studio 2013 and here is my code:

<asp:DropDownCheckBoxes ID="ddcbPSR" runat="server" UseSelectAllNode="false">
                <Style SelectBoxWidth="360" DropDownBoxBoxWidth="360" DropDownBoxBoxHeight="80" />
                <Texts SelectBoxCaption="Select PSR(s)" />
                    <asp:ListItem Text="Item 1" Value="0"></asp:ListItem>
And when I click on Item 1 in the list - I get that error.