In the classic prisoner's dilemma, the unique equilibrium occurs when both players betray one another. Why do rational players choose to defect? a. Each player will get a better outcome by defecting, regardless of the other player's decision b. Each player expects the other to cooperate, so they could get their best outcome by defecting c. Risk aversion makes each player suspect that the other will choose to defect d. The outcome when both players defect gives them both the highest possible payoff