单项选择题
A. It forces hot air out of the PC
B. The fan is easier to remove and clean
C. It forces cooler air into the power supply quickly
D. It forces cooler air across the motherboard
单项选择题 When Bob, a technician, powers up a desktop PC, the unit will repeat three short beeps and will not POST. Which of the following is MOST likely the problem?（）
单项选择题 Which of the following is the default location for user account files in Windows Vista?（）
单项选择题 A client reports that the cursor on their laptop moves to one corner of the screen and stays there when they try to use the keyboard joystick. Which of the following components will MOST likely need to be replaced to resolve the issue?（）