A pronoun that refers to more than one person place or thing

indefinite pronoun

Explanation:

refers to persons, places, things, or ideas in a more general way than a noun does

i believe it is the first choice (1.)

because the major theme is(“both the wild and civilization have rules.”)

and also as u said,( based on what buck learns within the call of the wild, "both the wild and civilization have rules".this is true of humans within society as well.

i think that the major difference is that it used to be modern