在窗体上画一个名称为Text1的文本框，要求文本框只能接收大写字母的输入，以下能实现该操作的事件过程是______。
A．Private Sub Text1_KeyPress(KeyAscii As Integer)
If KeyAscii＜65 Or KeyAscii＞90 Then
MsgBox"请输入大写字母"
KeyAscii=0
End If
End Sub
B．Private Sub Text1_KeyDown(Keycode As Integer, Shift As Integer)
If KeyCode＜65 Or Keycode＞90 Then
MsgBox"请输入大写字母"
KcyCode=0
End If
End Sub
C．Private Sub Text1_MouseDown(Button As Integer,
Shift As Integer, X As Single, Y As Single)
If Asc(Text1. Text)＜65 Or Asc(Text1. Text)＞90 Then
MsgBox"请输入大写字母"
End If
End Sub
D．Private Sub Text1_Change()
If Asc(Text1. Text)＞64 Or Asc(Text1. Text)＜91 Then
MsgBox"请输入大写字母"
End If
End Sub