How to add confirmation window

Hello,

I used below mentioned macro for locking teachers mark entry file. How to add a confirmation window like "Do you want to lock your data"?

Sub Verified()
ActiveSheet.Unprotect Password:=1357
Range("D3:F3").Select
Selection.Locked = True
Selection.FormulaHidden = False
Range("C5:F49").Select
Selection.Locked = True
Selection.FormulaHidden = False
ActiveSheet.Protect Password:=1357
ActiveWorkbook.Save
MsgBox ("Your data verified and saved successfully")
End Sub