Answer:
A reference group
Step-by-step explanation:
Reference groups are are set of people who are used as a standard for how to comply with social norms thereby influencing our ideas, values, behaviour, and appearance.
For example a reference group can be a set of people that have achieved a certain level of importance in a field by following a standard.
In the given scenario Blueberry Designs ads show a lifestyle that is sophisticated and timeless.
Those that follow the standards set by Blueberry designs can be said to be a reference group