单选

随着计算机应用范围的扩大,如何确保计算机的安全性显得日益重要。在常用的对文件进行安全性管理的措施中,(18)的主要任务是不允许未经核准的用户进入系统;(19)是通过系统管理员或文件主对文件属性的设置,来控制用户对文件访问。

  • A.系统级安全管理
  • B.用户级安全管理
  • C.目录级安全管理
  • D.文件级安全管理
参考答案
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