单项选择题
A. The drum is old and needs to be replaced.
B. The fuser is not coming up to the proper temperature.
C. The paper tray rollers are too tight.
D. The paper is damp due to humidity.
单项选择题 A user requires more storage space on their computer. After a technician installs a second IDE drive in the computer, the system will not recognize that there are any hard drives installed. Which of the following is the MOST likely cause of the problem?（）
单项选择题 Which of the following wireless technologies is backward compatible to receive all bands ofwireless communications?（）
单项选择题 Which of the following is used by BitLocker to lock an encryption key and protect data?（）