Students who only perform well when the team works together exemplify which concept?

The concept exemplified by students who only perform well when the team works together is known as the social facilitation effect. This phenomenon refers to the tendency of individuals to perform better on tasks when they are part of a group. The presence of others can enhance an individual's motivation and arousal, leading to improved performance, particularly for tasks that are familiar or well-practiced. In this case, the students thrive in a collaborative environment, indicating that the collective effort amplifies their individual capabilities.

The other concepts listed represent different dynamics within group behavior. Groupthink involves a scenario where the desire for harmony or conformity results in irrational or dysfunctional decision-making within a group. Social loafing refers to the tendency for individuals to exert less effort when working in a group compared to when working alone, which is the opposite of what the question describes. The synergistic effect highlights instances where the collective output of a team is greater than the sum of its individual members' contributions, but it isn't specifically focused on the performance variability based on individual reliance on teamwork.