Final answer:
The first filter used to evaluate attractiveness is physical attractiveness, as it is the most immediate and observable trait upon first encountering a person.While factors such as similarity, proximity, and reciprocal liking play significant roles in the formation and maintenance of relationships, they tend to come into play after the initial assessment based on physical attraction has occurred.
Step-by-step explanation:
The first filter people use to evaluate each other's attractiveness is d) Physical attractiveness. This is because initial judgments are often based on the most immediately observable traits, which in social encounters is the physical appearance of a person. While factors such as similarity, proximity, and reciprocal liking play significant roles in the formation and maintenance of relationships, they tend to come into play after the initial assessment based on physical attraction has occurred.