Rebooting the computer into safe mode (Option B) limits the processes and services that run, which can help in isolating and removing persistent malware that might be hiding in normal mode. Safe mode provides a cleaner environment to troubleshoot and remove malware.
* Restoring from a backup (Option A) may work but should be considered after attempts to clean the infection.
* Purchasing a new endpoint protection tool (Option C) is unnecessary at this stage since existing tools can be run in safe mode.
* Using system recovery (Option D) could potentially remove the infection, but it's a more drastic step that may not be necessary yet.
CompTIA A+ Core 2 References:
* 3.3 - Best practices for malware removal, including booting into safe mode