A junior administrator issues the following commands on a Linux server: The next day, the junior administrator is unable to edit the file. Which of the following would resolve this issue?

chmod 666 sets the file mode to rw-rw-rw-, granting read and write permission to the owner, group, and all others. If a prior command removed the owner's write bit (such as chmod 444 or chmod a-w), this command restores write access so the junior administrator can edit the file again. This is the most direct and correct fix for a permission-denied error when an owner attempts to write to a file they own but lack write permission on.

chmod $+x is not valid chmod syntax because $ is interpreted as a shell variable prefix, causing the command to fail or behave unexpectedly - it also targets execute permission rather than write permission.

chmod g+s sets the setgid bit on a file or directory, which affects group inheritance for new files in directories, and does not restore write access for the file owner.

chmod o+rwx grants full read, write, and execute permissions to 'others' (users outside the owner and group), but does not restore the owner's own write permission if that bit was removed.