What Lesson Do Neoliberal Institutionalists Learn from the Prisoner's Dilemma

What lesson do neoliberal institutionalists learn from the prisoner's dilemma?

A) If states confront each other repeatedly, they find it is in their self-interest to cooperate.
B) Self-interested actors will never cooperate, so states should work to obtain as much power as they can to protect themselves from other states.
C) States will never be able to cooperate on security issues.
D) Because of the goodness of human nature, less than optimal outcomes rarely occur when states interact.
E) The prisoner's dilemma can never accurately model international politics.