A.filea.txtis owned by another user and a regular user cannot change the permissions of another user's file.

B.filea.txtis a symbolic link whose permissions are a fixed value which cannot be charged.

C.filea.txthas the sticky bit set and a regular user cannot remove this permission.

D.filea.txtis a hard link whose permissions are inherited from the target and cannot be set directly.

E.filea.txthas the SetUID bit set which imposes the restriction that only the rootuser can make changes to the file.

A.File sizes

B.MD5 checksums

C.Timestamps

D.Inodes

E.GnuPG signatures

A.ln a.txt c.txt

B.ln -i 525385 c.txt

C.ln c.txt a.txt

D.ln -f c.txt a.txt

E.ln -h a.txt c.txt

A.

B..bashrc_history

C..bash_histfile
.history

D..bash_history

E..history_bash