单项选择题

对于如下程序,单击Co皿andl事件发生后,窗体上显示的内容为 ______。 Private Sub Command1_Click() Dim i As Integer,a a As Integer Do While i<20 Do While True If i Mod 10 = 0 Then Exit Do Else i=i-1 End If Loop i=i+11 a=a+1 Loop Print a End Sub

A.21
B.32
C.33
D.11