Final answer:
In the context of impression formation, categorization is the most fitting one-word description from the given options as it refers to how we organize and simplify our understanding of people.
Step-by-step explanation:
If I were to describe impression formation in just one word, the best fit from the provided options would be a) Categorization. This term refers to the process by which we organize information about people into categories to simplify our understanding of them. While impression formation may involve elements of the other options provided, such as stereotyping or generalization, these are more specific forms of cognitive biases or simplifications.
For example, when discussing cognitive biases, seeking out information that supports our stereotypes is known as confirmation bias. The term stereotype itself refers to a simplistic, firmly held belief about the characteristics of a group of people, which can be part of impression formation but isn't the sole process at play. In the context of problems and decision-making, becoming fixated on a single trait can show anchoring bias, while relying on a false stereotype to make a decision also demonstrates confirmation bias.
It is important to note that while generalizations can be descriptive of groups, they do not account for individual differences and are not normative statements that can be used to assign blame or credit.