单项选择题 A customer reports that the laser printer produces poor quality printouts. Having arrived onsite, the technician has a discussion with the customer and reviews some examples of their print jobs. Which of the following should the technician do NEXT? （）

单项选择题 A technician receives a boot error message OS not found. Which of the following should thetechnician check? （）

单项选择题 Which of the following features is only available with the Windows XP Professional version ascompared to the Windows XP Home version? （）