对窗体编写如下事件过程： Private Sub Form_MouseDown(Button As Integer，Shift As Integer,X As Single，Y As Single) If Button = 2 Then Print"AAAAA" End If End Sub Private Sub Form_MouseUp(Button As Integer，Shift As Integer，X As Single，Y As Single) Print "BBBBB" End Sub 程序运行后，如果单击鼠标右键，则输出结果为 ______。

A．AAAAA BBBBB

B．BBBBB

C．AAAAA

D．BBBBB AAAAA

鸡卵胚胎发育的部位主要是______，供应胚胎发育的营养物质主要来自于______，鸡卵要在已经______和适宜______ 条件下才能孵化出小鸡．