The technician should configure "Group Policy" (Option B) to enforce password complexity across the enterprise. Group Policy in a Windows environment allows administrators to manage various settings, including password policies, at a domain level. This can include enforcing complexity requirements (such as minimum length, use of uppercase, lowercase, and special characters), expiration times, and other security measures.

Account lockout policy (Option A) controls how many failed login attempts trigger a lockout but does not handle password complexity.

Two-factor authentication (Option C) is an additional security measure requiring a second form of authentication, but it does not enforce password policies.

Access control lists (Option D) define which users or systems have access to resources, not how passwords are managed.

CompTIA A+ Core 2 References:

2.6 - Configure workstation security best practices, including password complexity and group policies​.