GetChoiceFieldValues

public static List<string> GetChoiceFieldValues(this SPList list , string fieldName )
{
 try
 {
 SPFieldChoice field = (SPFieldChoice)list.Fields[fieldName];

 if (field == null || string.IsNullOrEmpty(fieldName))
 {
 return null;
 }

 List<string> ret = new List<string>();

 foreach (string str in field.Choices)
 {
 ret.Add(str);
 }

 return ret;
 }
 catch (Exception ex)
 {
 return null;
 }
 
}

List<string> myitems = myspList.GetChoiceFieldValues("CountryNames");