单项选择题

在窗体上画一个名称为Command1的命令按钮和3个名称分别为Labe11、Labe12、 Labe13的标签,然后编写如下代码: Private x As Integer Private Sub Command1_Click() State y As Integer Dim z As Integer n = 10 z = n+z y = y+z x = x+z Labe11.Caption = x Labe11.Caption = y Labe11.Caption = z End Sub程序运行后,连续3次单击命令按钮,则3个标签框中显示的内容分别是______。

A.10 10 10
B.30 30 30
C.30 30 10
D.10 30 30