A:  This will fill a list box with the names of the fields that are represented by indices.

procedure TForm1.Button1Click(Sender: TObject);
var
  i : integer;
begin
  listbox1.clear;
  Table1.IndexDefs.Update; {Make sure that IndexDefs is not empty.}
  for i := 0 to table1.indexdefs.count - 1 do listbox1.items.add(table1.indexdefs[i].fields);
end;