The system administrator is keeping local configuration file changes in RCS. What command will commit the file to RCS revision control AND keep a local, unlocked copy of the latest version of the…

The `ci file` command checks in the file but by default either removes the working copy or leaves it locked, which does not satisfy the requirement of keeping a local, unlocked copy.

`rcs commit` is not a valid RCS command for checking in files; `ci` is the correct command.

`rcs o` is not a recognized or standard RCS command for committing files or manipulating their lock status in this context.

The `ci` command checks in revisions to the RCS repository, and the `-u` option specifically instructs RCS to unlock the file and leave a new, unlocked working copy in the current directory after the check-in is complete.