单项选择题
A. Ensure the projector is receiving power
B. Verify the laptop is not running on battery
C. Toggle the function key for displays
D. Replace the projector cable with another
单项选择题 A user states that whenever they try to launch a certain installed application, they hear unusual whirring/clicking sounds from their machine and the application never loads. Which of the following components would a technician MOST likely need to replace?（）
单项选择题 Which of the following security threats are MOST likely prevented through user training?（）
单项选择题 Traffic coming across port 443 is for which of the following protocols?（）