在窗体上画一个通用对话框，其名称为CommonDialog1，然后画一个名为Command1的命令按钮，并编写如下事件过程： Private Sub Command1_ Click() CommonDialog1. Flags= cd10FNHideReadOnly CommonDialog1. Filter= "All Files (*.*) ｜*.*｜Text File" & _ "(*.txt) ｜*.txt ｜ Batch Files (*.bat)｜ *.bat" CommonDialog1. FilterIndex = 2 CommonDialog1. ShowOpen MsgBox CommonDialog1. FileName End Sub程序运行后，单击命令按钮，将显示一个“打开”对话框，此时在“文件类型”框中显示的是______ 。

A．Private Sub Command1_ Click() CommonDialog1. FileName = "SaveFile" CommonDialog1. Filter = "All Files ｜ *.* ｜*.txt *.txt｜ *.doc｜ *.doc" CommonDialog1. Filterlndex = 2 CommonDialog1. DialogTitle = "Save" CommonDialog1. Action = 2 End Sub
B．Private Sub Command1_Click() CommonDialog1. FileName = "SaveFile" CommonDialog1. Filter = "All Files ｜*.* ｜ *.txt｜*.txt｜*.doc｜*.doc" CommonDialog1. Filterlndex = 1 CommonDialog1. DialogTitle = "Save" CommonDialog1. Action = 2 End Sub
C．Private Sub Command1_ Click() CommonDialog1. FileName = "Save" CommonDialog1. Filter = "All Files ｜%* ｜*.txt｜*.txt｜*.doc｜*.doc" CommonDialog1. Filterlndex = 2 CommonDialog1. DialogTitle = "Save" CommonDialog1. Action = 2 End Sub
D．Private Sub Command1_ Click() CommonDialog1. FileName = "SaveFile" CommonDialog1. Filter = "All Files ｜*.*｜*.txt｜*.txt｜*.doc｜*.doc" CommonDialog1. Filterlndex = 1 CommonDialog1. DialogTitle = "Save". CommonDialog1. Action = 1 End Sub

A．在程序运行过程中能够增加或减少菜单项
B．使菜单项的Enabled 属性为False，则可删除该菜单项
C．弹出式菜单在菜单编辑器中设计
D．利用控件数组可以实现菜单项的增加或减少