Which of the following commands will create an archive file, named backup.tar, containing all the files from the directory /home?

No operation flag is given, so tar cannot determine whether to create, extract, or list, and the argument positions are also incorrect.

The archive filename and source path are swapped - this would attempt to create an archive named /home containing a file called backup.tar.

The -x flag signals extraction, not creation, so this would attempt to extract rather than create an archive, and the argument order is also reversed.

The -x flag signals extraction, not creation, so this command would try to extract backup.tar rather than create a new archive from /home.

tar -cf backup.tar /home uses -c to signal archive creation and -f to designate the output filename as backup.tar, followed by the source directory /home. The argument order is critical - the filename must immediately follow -f, and the source paths come last. This is the correct POSIX tar syntax for creating a new archive from a directory.