题目内容：

[单选题]在窗体上画一个名称为Commana1的命令按钮，然后编写如下程序： Dim SW As Boolean Function func(X As Integer)As Integer If X＜20 Then Y=X Else Y=20+X End If func = Y End Function Private Sub Form. MouseDown(Button As Integer,_ Shift As Integer,X As Single, Y As Single) SW = False End Sub Private Sub Form_MouseUp( Button As Integer,_ Shift As Integer ,X As Single, Y As Single) SW = True End Sub Private Sub Commandl_Click( ) Dim intNum As Integer intNum = InputBox(" ") If SW Then Print func(intNum) End If End Sub 程序运行后，单击命令按钮，将显示一个输入对话框，如果在对话框中输入25，则程序的执行结果为

A．输出0

B．输出25

C．输出45

D．无任何输出