It is a super simple task, this is one of possible approaches:
<asp:DropDownList ID="DropDownList1" runat="server"
DataSourceID="XmlDataSource1" DataTextField="Name" DataValueField="ID">
</asp:DropDownList>
<asp:XmlDataSource ID="XmlDataSource1" runat="server" DataFile="~/test.xml"
XPath="consumers/consumer"></asp:XmlDataSource>
Copy this code in a page and make sure that your file is called test.xml and that it is in the site root directory.
Cheers