Answer:
Reference group
Step-by-step explanation:
A reference group is the group where there is a people that compared for ourselves irrespective of the part of the group or not. In this in understand the social norms that can shape our values, ideas, attitudes, behavior, etc
Since in the given question it is mentioned that Tom has both direct and indirect influence with respect to his attitude and behavior while when he considered the purchase so this represent the reference group
hence, the same is to be considered