You want to append a tar file if the on-disk version of the tar file has a modification date more
recent than its copy in the tar archive. Which of the following commands will you use to
accomplish the task?

A.
tar -x

B.
tar -t

C.
tar -u

D.
tar -c

Explanation:

The tar -u command is used to append a tar file if the on-disk version of the tar file has a
modification date more recent than its copy in the tar archive.
Answer option B is incorrect. The tar -t command is used to list the contents of an archive.
Answer option A is incorrect. The tar -x command is used to extract the files from an archive.
Answer option D is incorrect. The tar -c command is used to create a new archive of specified
files.