Final answer:
The characteristic that distinguishes stressed sideliners from the other group is their position in the social hierarchy.
Step-by-step explanation:
The characteristic that distinguishes stressed sideliners from the other group is their position in the social hierarchy. According to neuroscientists Robert Sapolsky and Carol Shively, position in the social hierarchy predicts stress, mental health status, and disease. Research on non-human primates has shown that individuals who are stigmatized or ostracized experience higher levels of stress, which can lead to negative health outcomes.