Final answer:
Darren is displaying self-regulation by controlling his anger and taking a constructive approach when dealing with his friend's cheating in a game.
Step-by-step explanation:
Darren is demonstrating self-regulation in his actions. Self-regulation involves controlling one's emotions and behaviors to achieve goals and adapting to the feedback received from the environment. In Darren's case, despite feeling irritated when his friend cheats in a game, he manages to control his anger and instead takes the situation as an opportunity to explain why cheating is not good behavior. This demonstrates not just restraint, but also a goal-oriented approach to social interactions, which is a hallmark of self-regulation capabilities.