Aqui mi código:
<?xml version="1.0" encoding="iso-8859-1"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<%@ Page Language="VB" ContentType="text/html" ResponseEncoding="iso-8859-1" %>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Unbenanntes Dokument</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
</head>
<body>
<asp:DropDownList ID="dplRangoEdad" runat="server" AppendDataBoundItems="true" CssClass="caja" Width="145px">
<asp:ListItem Value="0">--Seleccionar--</asp:ListItem>
<asp:ListItem Value="1">Adulto</asp:ListItem>
<asp:ListItem Value="2">Joven</asp:ListItem>
<asp:ListItem Value="3">Niño</asp:ListItem>
</asp:DropDownList>
</body>
</html>