Liste de validation avec une condition

Private Sub ComboBox3_Change()

Range("A12:A21").Select
    If Range("C1") = True And Range("A8") = True Then
    With Selection.validation
        .Delete
        .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:= _
        xlBetween, Formula1:="=plageSTE"
        .IgnoreBlank = True
        .InCellDropdown = True
        .InputTitle = ""
        .ErrorTitle = ""
        .InputMessage = ""
        .ErrorMessage = ""
        .ShowInput = True
        .ShowError = True
    End With
    Else
    
    If Range("C2") = True And Range("A8") = True Then
    With Selection.validation
        .Delete
        .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:= _
        xlBetween, Formula1:="=plageSFDL"
        .IgnoreBlank = True
        .InCellDropdown = True
        .InputTitle = ""
        .ErrorTitle = ""
        .InputMessage = ""
        .ErrorMessage = ""
        .ShowInput = True
        .ShowError = True
    End With
   Else
   
     If Range("C3") = True And Range("A8") = True Then
     With Selection.validation
        .Delete
        .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:= _
        xlBetween, Formula1:="=plagePLB"
        .IgnoreBlank = True
        .InCellDropdown = True
        .InputTitle = ""
        .ErrorTitle = ""
        .InputMessage = ""
        .ErrorMessage = ""
        .ShowInput = True
        .ShowError = True
    End With
   
   End If
   End If
   
End Sub

Function RechFind(ByVal Cle As String, ByVal WkbN As String, ByVal WksN As String, ByVal Plage As String, ByRef TBadress() As Variant) As Long
Dim Cherche, Ix As Long, PrAddress
    
    If Range("C1") = True Then
    A = "STE"
    Else
    If Range("C2") = True Then
    A = "SFDL"
    Else
    If Range("C3") = True Then
    A = "PLB"
    Else
    End If
    End If
    End If
    
    
    With Workbooks(WkbN).Sheets(A).Range(Plage)
        Set Cherche = .Find(Cle)
        If Not Cherche Is Nothing Then
            PrAddress = Cherche.Address
            Do
                ReDim Preserve TBadress(Ix)
                TBadress(Ix) = Cherche.Address
                Set Cherche = .FindNext(Cherche)
                Ix = Ix + 1
            Loop While Not Cherche Is Nothing And Cherche.Address <> PrAddress
        End If
    End With
    'nombre d'occurence(s) trouvée(s), Retour 0 si aucune occurence
    RechFind = Ix
    Set Cherche = Nothing 'Libére la mémoire occupée par l'objet.
End Function

Private Sub ComboBox3_Change()
Dim R As Long, TB()
Dim i As Integer

    If Range("C1") = True Then
    A = "STE"
    Else
    If Range("C2") = True Then
    A = "SFDL"
    Else
    If Range("C3") = True Then
    A = "PLB"
    Else
    End If
    End If
    End If
    
    Sheets("Menus déroulants").Range("A2:A1000").ClearContents
    R = RechFind(Range("C6"), ThisWorkbook.Name, Sheets(A).Name, Range("A2:A1000").Address, TB())
    If R > 0 Then
        For i = 0 To R - 1 ' ou ubound(TB)
            'exemple
            Sheets("Menus déroulants").Cells(i + 2, 1) = Range(TB(i)).Row
        Next i
    End If
End Sub