Which old legacy application provides remote lookup services to find users on a Linux system?

The correct choice, finger, is an old legacy application that allows users to obtain information about other users on a Linux system. It provides functions such as looking up users, checking their last login times, and viewing their status. The command is often used in network environments to query user information from other systems, helping users identify whether someone is currently logged in or their last activity.

This application fits the description of providing remote lookup services, as it actively queries user data over the network. It reflects an earlier approach to user management and communication within Unix-based and Linux systems. Despite its fading usage with modern user management tools and security practices, finger remains a foundational tool in understanding legacy systems and user information retrieval processes.

In contrast, telnet is primarily a remote login protocol used to access a command line on a remote system, kinit is related to authentication in Kerberos networking, and vim is a text editor with no functionality concerning user lookup. Understanding the specific capabilities of these applications clarifies how finger serves the unique role of user information retrieval within Linux systems.