Two firms are in a classic prisoner's dilemma type of competition. The Nash equilibrium for a one-shot game is for both firms to attack which results in lower payoffs for both firms than if they both choose to cooperate. Which of the following is most likely to result in them both choosing to cooperate? Group of answer choices The firms make a verbal agreement with each other to cooperate. They're competitive firms so nothing could get them to cooperate. The game is repeated for more than one period and the firms are worried that attacking will prompt their rival to attack in future periods. The game is repeated for some unknown number of periods and the firms are worried that attacking will prompt their rival to attack in future periods. The game is repeated for more than one period and they want to be viewed as being a good corporate partner