Answer:
Secondary group
Step-by-step explanation:
We say that group is a secondary group when we talk about a group of people that gather themselves in an impersonal way.
Although group members may have some similar interests, the purpose of the group is about the task instead of the relationships, so this group is task-oriented
In this example, although these people met in a sociology class, they see each other only occasionally (they don't have a close relationship) and they gather to study together and pool their notes (they are task-oriented).
Thus, sociologists would term them a secondary group.