Sub Index()
Dim Str$, Path_A$, Path_B$
Dim FSO As Object
Path_A = ThisWorkbook.Path & "\А\" 'Откуда
Path_B = ThisWorkbook.Path & "\Б\" 'Куда
Str = Dir(Path_A & "*.txt")
Set FSO = CreateObject("Scripting.FileSystemObject")
Do While Str <> ""
    If FSO.GetFile(Path_A & Str).Size < 2000 Then 'файлы меньше 2кБ
        FSO.GetFile(Path_A & Str).Move Path_B
    End If
    Str = Dir 'Следующий файл
Loop
MsgBox "Перемещение выполнено", vbInformation, "Пример"
End Sub

Sub List()
Dim uniq As New Collection
Dim iLastRow As Long
Dim i As Long
Dim arr()
iLastRow = Cells(Rows.Count, 3).End(xlUp).Row
iLastRow = IIf(iLastRow < 7, 7, iLastRow)
    For i = 7 To iLastRow
        On Error Resume Next
        uniq.Add Cells(i, 3), CStr(Cells(i, 3))
    Next
ReDim arr(1 To uniq.Count)
    For i = 1 To uniq.Count
        arr(i) = uniq(i)
    Next i

With Cells(3, 3).Validation
    .Delete
    .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:= _
    xlBetween, Formula1:=Join(arr, ",")
    .IgnoreBlank = True
    .InCellDropdown = True
    .ShowInput = True
    .ShowError = False
End With
End Sub

=ДВССЫЛ("'" & A1 & "'!A$" & 1)

СЧЁТЕСЛИ(B3:G33;"R")