Final answer:
David and Melanie's actions of preparing for their baby by setting up a nursery and buying essentials are an example of a role transition ritual, highlighting anticipatory socialization for new life roles.
Step-by-step explanation:
In the scenario where David and Melanie are preparing for their first baby by decorating a nursery, buying toys, and gathering baby essentials, they are engaging in a role transition ritual. This type of consumer behavior is emblematic of the preparations and actions individuals take as they anticipate stepping into a new life role, which in this case is parenthood. These behaviors are part of anticipatory socialization, defined as the process of preparation for future life roles that individuals undergo as they adapt to changing social structures and expectations. When David and Melanie set up the nursery and purchase baby products, they are not only getting ready for the baby's physical arrival but also socially and psychologically preparing themselves to embrace their new identities as parents.