单项选择题 A virus scanner is running on a computer and scans all files currently in use. Why should a full scan be performed periodically?（）

单项选择题 Which of the following commands will show all active TCP/IP network connections?（）

单项选择题 A technician is able to connect to the Internet but cannot connect to a remote machine through Remote Desktop in Windows XP. Each time the technician attempts to connect to a remote location, the software times out. Which of the following is the MOST likely problem?（）