参考答案：B

解析： 本题考查事件监听器的概念。窗口事件接口WindowListener有几个关键方法，应该注意，如public void windowClosing(WindowEvent e)是把退出窗口的语句写在本方法中；pubic void windowOpened(WindowEvent e)是窗口打开时调用；public void windowClose d(indnwEvent e)是窗口关闭时调用，选项B正确；public void windowIconified(WindowEve nt e)是窗口图标化时调用；public void windowDeiconified (WindowEvent e)是窗口非图标化时调用；public void windowActivated (WindowEvent e)是窗口激活时调用：public void windowDeactivated(WmdowEvent e)是窗口非激活时调用。