单项选择题 In order to ensure there is proper airflow in a new computer, which of the following should be performed?（）

单项选择题 A customer purchased a new PC with Windows XP but wants to run a program designed forWindows 98. Which of the following will allow this program to run under Windows XP?（）

单项选择题 A technician installed a new video card on a motherboard which has onboard video. When the monitor was plugged into the new card and the power was turned on, a no signal message appeared on the monitor. Which of the following is MOST likely the issue?（）