Booting the system into safe mode is the correct answer because it starts the system with a minimal set of drivers and services. Malware often relies on specific services to run, and by booting into safe mode, you may prevent the malware from loading, which allows the anti-malware software to detect and remove it more effectively. Rebooting the system normally or creating a new user account could allow the malware to actively resist removal efforts. Running a disk cleanup utility might assist in removing temporary files that could contain malware, but it does not directly impact the anti-malware software's ability to detect and remove active infections.