单项选择题 A user reports that their onboard RJ-45 jack is damaged and will no longer function. Which of the following will provide this jack as an alternative to replacing the motherboard?（）

单项选择题 A technician does not have power to a PC. Which of the following tools should the technician use to check for electricity?（）

单项选择题 Which of the following tools can be used to test if a 24-pin power cable is outputting correct voltage?（）