Answer: sometimes when individuals act independently in their own self-interest, everyone is worse off than if they had cooperated (A)
Step-by-step explanation:
The prisoner's dilemma is an example of a game which is analyzed in game theory which shows that two completely rational individuals may not cooperate, even though it will have been in their best interest to cooperate.
In Prisoner's dilemma, when individuals act independently sometimes in their own self-interest, it makes everyone worse off than when they could have cooperated.