Which of the following statements is true about the 80/20 rule （Select all that apply）？（）

• A、20 percent of the traffic on a network segment should be local.
• B、no more than 20 percent of the network traffic should be able to move across a backbone.
• C、no more than 80 percent of the network traffic should be able to move across a backbone.
• D、80 percent of the traffic on a network segment should be local.