单项选择题 What can be specified in IP VACLs?（）

单项选择题 A Cisco Catalyst switch is part of the CIS network. As an experienced network administrator, you are thinking of filtering the traffic within VLANI00 with the use of a VACL named "test" on that switch. Which of the following command will enable that?（）

多项选择题 avoid Layer 2 loops. Which two of the following are most probably the reasons for that preference?（）