What psychological bias leads to the assumption that someone with one positive trait will have others?

The correct answer is the Halo Effect. This psychological bias occurs when a person's overall impression of someone positively influences their feelings and thoughts about that individual's specific traits. For example, if someone is perceived as physically attractive, people might also assume they possess other positive characteristics, such as intelligence or kindness, even without evidence to support these assumptions.

The Halo Effect is significant in various social contexts, including job interviews and performance evaluations, where an overall positive impression can lead to an uncritical acceptance of a person's abilities or character.

In contrast, the other biases mentioned do not specifically cause the assumption that a person with one positive trait has additional positive traits. Confirmation Bias relates to the tendency to search for, interpret, and remember information that confirms one's existing beliefs. Self-Serving Bias refers to the inclination to attribute positive events to one's own character while attributing negative events to external factors. Lastly, Attribution Bias involves the tendency to favor internal attributions for others' behavior while favoring external attributions for one's own behavior. None of these directly encapsulates the idea that one positive trait leads to the assumption of additional positive traits, which is the essence of the Halo Effect.