Which of the following will change the group that is associated with a file?

chmod changes permission bits (read, write, execute) on a file but does not affect which user or group owns it.

'chmod -w' removes write permission from a file's permission bits and has no effect on group ownership.

chown (change owner) accepts an optional group component in the form 'chown owner:group file' or 'chown :group file', allowing the file's associated group to be changed. While chgrp is the dedicated group-change command, chown is the answer here as it is the only listed command capable of changing group association.

'ls -g' is a listing flag that displays group information in output but does not modify any file attributes.