双击窗体中的对象后，Visual Basic将显示的窗口是

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．能接收用户输入的数据，但不会返回任何信息
B．能接收用户输入的数据，并能返回用户输入的信息
C．既能用于接收用户输入的信息，又能用于输出信息
D．专门用于输出信息