单项选择题
Which of the following cable types has a MAXIMUM transmission speed of 10Mbps?（）
A. CAT6 B. CAT5 C. Single-mode fiber D. CAT3
单项选择题 Which of the following layers is associated with the physical hardware address of a network node?（）
单项选择题 Which of the following OSI model layers is used for logical addressing?（）
单项选择题 Which of the following is the MOST efficient way to troubleshoot network problems?（）
