When trying to print, a is offline.

When a printer is offline for one user but works for others, the issue often lies in the user's print queue settings, such as a paused queue or failed print jobs. Checking and clearing the print queue can resolve the problem.

Why Not B (Check the printer's IP address): If other users can print, the printer’s IP address is not the issue.

Why Not C (Check the user's network settings): Network issues are unlikely if the user can access other resources on the network.

Why Not D (Check the printer's firmware version): Firmware issues would affect all users, not just one.

CompTIA A+ Exam Reference: Core 2 (220-1102), Section 4.4, printer troubleshooting​.