现有如下程序:
Public Sub display(x As Control)
If TypeOf x Is Label Then
x Caption="计算机等级考试"
Else
xPicture=LoadPicture("pic.jpg")
End If
End Sub
Private Sub Label1_Click()
Call display(Label1)
End Sub
Private Sub Picture1_Click()
Call display(Picture1)
End Sub
对以上程序,下列叙述中错误的是______。