Which of the following commands extracts the contents of the compressed archive file1.tar.gz?

The -c flag creates a new archive rather than extracting; -czf would compress and create file1.tar.gz, the opposite of extracting it.

This command omits the -z flag needed to handle gzip decompression, and references an incorrect filename (file1.gz) that does not match the actual archive file1.tar.gz.

The flags -x (extract), -z (filter through gzip), and -f (use the named file as the archive) together correctly decompress and unpack a .tar.gz archive. Running 'tar -xzf file1.tar.gz' fully restores all files stored in the compressed tar archive.

The --extract flag alone without -z and a proper -f filename argument cannot decompress and extract a gzip-compressed tar archive correctly.

'detar' is not a valid Linux command and no such standard utility exists for extracting tar archives.