Xml datalist hoew to delete parent element on click delete comand button

protected void btnSubmit_Click(object sender, EventArgs e)
    {
        XmlDocument xmldoc = new XmlDocument();
        xmldoc.Load(Server.MapPath("news.xml"));
        XmlElement parentelement = xmldoc.CreateElement("Comments");
        XmlElement name = xmldoc.CreateElement("Name");
        name.InnerText = txtName.Text;
        XmlElement Description = xmldoc.CreateElement("Description");
        Description.InnerText = txtComments.Text;
        XmlElement date = xmldoc.CreateElement("Date");
        date.InnerText = DateTime.Now.ToString();
        parentelement.AppendChild(name);
        parentelement.AppendChild(Description);
        parentelement.AppendChild(date);
        xmldoc.DocumentElement.AppendChild(parentelement);
        xmldoc.Save(Server.MapPath("news.xml"));
        Clear();
    }