在窗体上画一个名称为CommonDialog1的通用对话框，一个名称为Command1的命令按钮，要求单击命令按钮时，打开一个保存文件的对话框，该窗口的标题为“Save”，缺省文件名称为“SaveFile”，在“文件类型”栏中显示*txt，则能够满足上述要求的程序是

A．Private Sub Command1_Click ( ) CommonDialog1．FileName="SaveFile" CommonDialog1．Filter="AllFiles|*.*|(*.txt)|*.txt|(*.doC)|*.doc" CommonDialog1．FilterIndex=2 CommonDialog1．DialogTitle="Save" CommonDialog1．Action=2 End Sub

B．Private Sub Command1_Click ( ) CommonDialog1．FileName="SaveFile" CommonDialog1．Filter="AllFiles|*.*|(*.txt)|*.txt|(*.do C)|*.doc" CommonDialog1．FilterIndex=1 CommonDialog1．DialogTitle="Save" CommonDialog1．Action=2 End Sub

C．Private Sub Command1 Click ( ) CommonDialog1．FileName="Save" CommonDialog1．Filter="AllFiles|*.*|(*.txt)|*.txt|(*.do C)|*.doc" CommonDialog1．FilterIndex=2 CommonDialog1．DialogTitle="SaveFile" CommonDialog1．Action=2 End Sub

D．Private Sub Command1 Click ( ) CommonDialog1．FileName="SaveFile" CommonDialog1．Filter="AllFiles|*.*|(*.txt)|*.txt|(*.do C)|*.doc" CommonDialogl.FilterIndex=1 CommonDialog1.DialogTitle="Save" CommonDialog1．Action=1 End Sub