下列不属于软件工程的3个要素的是

A．Private Sub Form_MouseDown(Button As Integer，Shift As Integer,_X As Single，Y As Single)
　　If Button=2 Then PopupMenu Bs，2
End Sub
B．Private Sub Form_MouseDown(Button As Integer，Shift As Integer,_X As Single，Y As Single)
　　PopupMenu Bs
End Sub
C．Private Sub Form_MouseDown(Button As Integer，Shift As Integer,_X As Single，Y As Single)
　　PopupMenu Bs，0
End Sub
D．Private Sub Form_MouseDown(Button As Integer，Shift As Integer,_X As Single，Y AS Single)
　　If(Button=vbLeftButton)Or(Button=vbRightButton)Then PopupMenu Bs
End Sub

A．算法程序的长度
B．算法程序中的指令条数
C．算法程序所占的存储空问
D．算法执行过程中所需要的存储空间