There are three main administration files in the Unix operating system which are: $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_,\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_,$ and $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.$

Group of answer choices

$/$etc$/$passwd$,/$etc$/$shadow$,$ and $/$etc$/$group$.$

$/$etc$/$users$,/$etc$/$folders$,$ and $/$etc$/$files$.$

$/$etc$/$usernames$,/$etc$/$shadow$,$ and $/$etc$/$files$.$

$/$etc$/$users$,/$etc$/$passwd$,$ and $/$etc$/$shadow$.$