Which service allows a UNIX box to become a full member of an NT domain, unifying Linux/UNIX and Windows NT account management?

Winbind is the correct choice for enabling a UNIX system to become a full member of an NT domain, providing a means to unify account management for both Linux/UNIX and Windows NT environments. It is part of the Samba suite and facilitates interaction with Windows servers by allowing UNIX systems to authenticate users and retrieve user information from the Active Directory integrated into the NT domain.

When Winbind is configured, it enables UNIX systems to use Windows user accounts and groups seamlessly, thus providing a cohesive environment where users can log in using their Windows credentials on a UNIX system. This integration is critical for organizations that operate in mixed environments, as it simplifies user management and improves security by centralizing authentication processes.

The other options serve different purposes in network and account management. PAM (Pluggable Authentication Modules) is focused primarily on the authentication process and can work with various services but doesn't specifically link UNIX accounts to an NT domain. NIS (Network Information Service) is used for managing user accounts and other related information in UNIX but does not integrate with NT domains. OpenLDAP is a directory service that can be used for user authentication but does not connect directly to Windows NT domains like Winbind does. Therefore, Winbind stands out as the essential service for bridging the gap between