A technician needs to disable guest log-ins on domain-joined desktop machines.

Comprehensive and Detailed Explanation From Exact Extract:

Group Policyis the standard administrative tool for enforcing security and configuration settings across domain-joined systems, including disabling guest accounts.

FromQuentin Docter – CompTIA A+ Study Guide:

“Disabling guest accounts and applying consistent security policies across multiple machines is best achieved through Group Policy on a Windows domain.”