The Textbook Describes Research by Kelley and Stahelski, Who Asked

The textbook describes research by Kelley and Stahelski, who asked participants, before they played the prisoner's dilemma game, whether they thought competition or cooperation was the goal of the game.How did the participants' beliefs affect the outcomes of the game?

A) As long as one person wanted to cooperate, both players were likely to cooperate.
B) Competitors made everyone more competitive, even those initially inclined to cooperate.
C) Competitors assumed their partners wanted to cooperate, and played the game to take advantage of them.
D) Participants' goals did not influence how they played the game after the first few trials.