在窗体上画一个名称为Command1的命令按钮和3个名称为Label1、Label2、Label3的标签,然后编写如下程序段: Private x As Integer Private Sub Command1_Click( ) Static y As Integer Dim z As Integer n =10 z = n+z y=y+z x=x+z Label1. Caption = x Label2. Caption = y Label3. Caption = z End Sub 运行程序,连续3次单击命令按钮后,则3个标签中显示的内容是( )。
A.10 10 10
B.30 30 30
C.30 30 10
D.10 30 30