Final answer:
The technician wants to enter Safe Mode to troubleshoot because it loads only the minimum drivers and services, preventing third-party applications from running.
Step-by-step explanation:
The BEST reason the technician wants to enter Safe Mode to begin troubleshooting is because Safe Mode loads only the minimum amount of drivers and services to start the system (option a). When a user's computer freezes to a blue screen during boot, it may be caused by a conflict with a device driver or incompatible software. By entering Safe Mode, the technician can isolate and troubleshoot the issue by preventing all third-party applications from running, allowing them to determine if the problem is caused by a driver or software conflict.