单项选择题 A user is having problems printing. The technician believes the printer may be out of ink. Which of the following troubleshooting steps should be performed NEXT?（）

单项选择题 A user is currently running Windows XP Media Center 32-bit and wants to upgrade to WindowsVista. An in-place upgrade is required. Which of the following versions can be used to accomplish this?（）

单项选择题 Which of the following should be completed NEXT, after testing the theory of probable cause?（）