单项选择题
A customer reports to Karen, a technician, that he is experiencing problems with the display after his computer is fully booted but reports seeing the BIOS splash screen during boot. Which of the following would MOST likely be the cause?（）
A. The video cable is incorrectly attached. B. A corrupted or incorrect video driver is installed. C. An incorrect video card is installed in the computer. D. The video card is defective and needs to be replaced.
单项选择题 Which of the following command line utilities can Karen, a technician, use to check for open ports?（）
单项选择题 An alternative to plain old telephone service (POTS) would be:（）
单项选择题 Which of the following commands would be used to display hidden files?（）
