Final Answer:
The idea that people develop relationships with those of similar levels of attractiveness is referred to as a) Homophily.
Step-by-step explanation:
Homophily suggests that individuals tend to form connections with others who share similar characteristics, such as attractiveness levels.
This phenomenon is rooted in the inclination for people to be drawn to those who resemble them in certain aspects, which can include physical attractiveness. Psychologically, people often feel more comfortable and relate better to others who possess comparable qualities or traits.
This doesn't imply that relationships are solely based on physical appearance; rather, it encompasses a broader spectrum of similarities, including attitudes, interests, and backgrounds.
Homophily extends beyond mere physical attractiveness and can encompass various shared attributes that foster rapport and compatibility between individuals.
Consequently, this tendency contributes significantly to the formation and development of social connections and relationships among people.
Hence, therefore option a) is correct.