设已经在菜单编辑器中设计了窗体的快捷菜单,某顶级菜单为a1,且取消其"可见"属性。运行时,可以使快捷菜单的菜单项响应鼠标左键单击和右单击的事件过程是______。
A.
Private Sub Form_Mouse Down(Button As Integer,Shift As Integer,_X As Single,
B.
Private Sub Form_Mouse Down(Button As Integer,Shift As Integer,_X As Single,
C.
Private Sub Form_Mouse Down(Button As Integer,Shift As Integer,_X As Single,
D.
Private Sub Form_Mouse Down(Button As Integer,Shift As Integer,_X As Single,