设窗体上有一个Picturel图片框，要求在图片框中的指定位置(坐标为(500，300))输出“OK”，下面可以实现这一功能的事件过程是 A: Private Sub Form_Click() Picture 1．CurrentX=500 Picture 1．CurrentY=300 Picture 1．Print"OK" End Sub B: Private Sub Form_Click() Picturel．Left=500 Picturel．Top=300 Picture 1．Print"OK" End Sub C: Private Sub Form_Click() Picture 1．CurrentX=500 Picture 1．CurrentY=300 Print"OK" End Sub D: Private Sub Form_Click() Picturel．Left=500 Picturel．Top=300 Print"OK" End Sub