单项选择题
A. They are using the wrong WEP key.
B. They have been infected with malware.
C. They have lost Internet connectivity.
D. They need to update their network device drivers.
单项选择题 A user states they receive a message Boot device not found half of the time they boot their system.Which of the following is the MOST likely cause? （）
单项选择题 A user reports that their system is starting to run slower, especially when opening large local files. The system has sufficient RAM for the users applications, but the hard drive seems to have higher than normal activity when opening large files. Which of the following would be the BEST tool to diagnose and troubleshoot this problem? （）
单项选择题 A customer reports they are unable to connect to any computers outside of the office and they are unable to connect to the Internet. When the technician runs ipconfig, the customer gets the following output: IP address169.254.2.4 Subnet Mask.255.255.0.0 Default Gateway. Which of the following could be causing the issue?（）