Which of the following is an approach to detect and otherwise avoid "insider attacks" such as logic bombs, etc.?

Question $6$ options:

Use software archiving and reporting tools.

Avoid having individuals be single points of failure for backups, etc.

Use code walk$-$throughs to go over code line$-$by$-$line, checking for errors, etc.

All of the other choices $($except "None of the other choices"$)$

None of the other choices.