单项选择题

在窗体上画一个名称为Command1的命令按钮,然后编写如下事件过程:
Private Sub subl(ByVal x As Integer, ByVal y As Integer, ByVal z As Integer)
z=x*x+y*y
End Sub
Private Sub Command1_Click()
Dim a As Integer
a=8
Call subl(1, 2,

A.
&nb