You need to move a database in between servers. You need to guarantee database users will be able to login in the database with a minimum of management effort. Select the BEST answer.

Application roles are used to grant specific permissions to applications rather than to authenticate end users, and they do not solve the portability problem when moving a database between servers.

Database users, specifically contained database users, store authentication credentials within the database itself rather than relying on server-level logins. When the database is moved to a new server, the users and their credentials travel with the database, eliminating the need to recreate server logins and remap user SIDs on the destination server.

Server logins are defined at the instance level and do not travel with the database when it is moved; on the new server, orphaned users would result because the SIDs of the logins may not match, requiring manual remapping effort.

Server roles are instance-level security principals used to group server-level permissions and do not move with the database, so they provide no benefit for ensuring user access after a database migration.