Ancient hunter-gatherers developed instincts that stigmatized selfishness, and voluntary cooperation was encouraged as well, whether it be within the group or also with outsiders.

(A) selfishness, and voluntary cooperation was encouraged as well, whether it be within the group or
(B) selfishness, encouraging voluntary cooperation as well, both within the group but
(C) selfishness and also encouraging voluntary cooperation, within the group and
(D) selfishness and they encouraged voluntary cooperation, whether it be within the group or
(E) selfishness and encouraged voluntary cooperation, not only within the group but

OA: Later