单选题 在窗体上画—个名称为Text1的文本框，并编写如下程序： Private Sub Form_Load() Show Text1.Text=" " Text1.SetFocus End Sub Private Sub Form_MouseUp(Button As Integer,Shift As Integer,X As Single,Y As Single) Print "程序设计" End Sub Private Sub Text1_KeyDown(KeyCode As Integer,Shift As Integer) Print "Visual Basic"； End Sub 程序运行后，如果按A键，然后单击窗体，则窗体上显示的内容是 ______。