Dim ABC As String
If Range("A2").Value = 1 Then
    ABC = Range("C2") & ".xls"
ElseIf Range("A2").Value = 2 Then
    ABC = Range("C2") & ".xlsx"
ElseIf Range("A2").Value = 3 Then
    ABC = Range("C2") & ".xlsm"
Else
    ABC = Range("C2") & ".txt"
    End If

Dim XYZ As String   'renomear ABC por XYZ
If Range("A2").Value = 1 Then
    XYZ = Range("C2") & ".xls"
ElseIf Range("A2").Value = 2 Then
    XYZ = Range("C2") & ".xlsx"
ElseIf Range("A2").Value = 3 Then
    XYZ = Range("C2") & ".xlsm"
Else
    XYZ = Range("C2") & ".txt"
    End If