单项选择题

给出下面的程序：Private Sub Command1_ Click() Dim Check, Counter Check= True: Counter = 0 do do while Counter ＜ 20 Counter = Counter +1 if Counter = 10 then Check=False exit do End if Loop Loop until Check=False MsgBox CounterEnd Sub 程序最后弹出的消息对话框的内容是______。