A: dir followed by a single letter.
C: dir followed by any characters ending with a.
D: dir followed by any characters, then character b, then one single character.
only dirabc matches

The sulog file,/var/adm/sulog,is a log containing all attempts (whether successful or not) of the su command. An entry is added to the sulog file every time the su command is executed. The fields in sulog are: date,time,successful (+) or unsuccessful (-),port,user executing the su command,and user being switched to. In the preceding example,all su attempts were successful,except for the attempt on 2/23 at 20:51,when user pete unsuccessfully attempted to su to user root.
Look for entries where an unauthorized user has used the command inappropriately. The following entry shows a successful (indicated by +) su from user userid to root.
SU 03/31 12:52 + pts/0 <userid>-root

First the full backup must be restored. This would be the Sunday backup.
Then the last incremental backup must be restored. This would be the Wednesday backup.
Before restoring the Wednesday incremental file system snapshot,the most recent
snapshot must first be rolled back.
By exclusion D) would be best answer even though it is incomplete.

Explanation/Reference:
Explanation:
In the Bourne Again, C, Korn, TC, and Z shells, the tilde (~) is used as a shortcut for specifying your home directory.
cd -
It's the command-line equivalent of the back button (takes you to the previous directory you were in).
Note:
To make certain that you are in your home directory, type the cd (change directory) command. This command moves you to your home (default) directory.