单项选择题
A. There is a loose object in the case.
B. An optical drive drawer is open.
C. The computer case was opened.
D. An attacker hacked into the system.
单项选择题 A technician has just installed an upgraded graphics card. The computers power turns off before itfinishes booting. Which of the following is the cause of the problem? （）
单项选择题 A user is trying to boot a desktop PC from their A: drive. Which of the following devices is the userdescribing？（）
单项选择题 A technician is troubleshooting a WLAN card in a laptop. The wireless infrastructure is 802.11g. TheWLAN card is showing connected at 11Mbps. Which of the following would be the BEST reason why theWLAN card is performing at that speed? （）