unable to store list in selected list

public SelectList GetAllprofsssinList()
{
   var PList = new List<professional();>

   ds = dropdown.GetDropDownList();
   List<SelectListItem> lstProfessional = new List<SelectListItem>();

   for (int record = 0; record <= ds.Tables[1].Rows.Count - 1; record++)
   {
      dynamic row = ds.Tables[1].Rows[record];

      // adding records to list of professional
      lstProfessional.Add(
          new SelectListItem  
          {  
             Text = Convert.ToString(row["ID"]), 
	         Value = Convert.ToString(row[DescriptionName]
          });
   }

  // generate SelectList object
  SelectList testList = new SelectList(lstProfessional);

  // returning list
  return testList;
}