单项选择题 A client has been unable to fix corruption of system files and does not have a backup or an Automated System Recovery (ASR) disk. Which of the following is the BEST action to take next? （）

单项选择题 A system powers on, begins POST, displays the BIOS version information and then hangs with the error message Error loading operating system. Which of the following is MOST likely cause of this issue? （）

单项选择题 After moving files from one folder to another, the technician cannot access them. Which of the following MUST the technician do to regain access to these files?（）