Answer:
reference group
Explanation:
Reference group refers to the subjects that is used as some sort of 'Standard'. Celebrities often used as refrence group to know things such as trends and styles.
Because Marketing team often used Celebrities to endorse their product. By having popular celebrities holding their purse, the company above make the watcher thing that the purse is something that is currently in trend or something that is 'cool; . This will explain the increase in sales.
