单项选择题 A server keeps rebooting at various times throughout the day. Which of the following tools wouldBEST help to diagnose this issue?（）

单项选择题 After testing a new 100BaseTX cable, the technician determines that only pairs 4, 5, 7, and 8 are straight-thru wires. Which of the following MOST likely describes this cable type?（）

单项选择题 Which of the following is typically used In an LAN environment?（）