This social group would best be described as a small group.
Step-by-step explanation:
A group with minimum of three members is known as small group. If the group has more than fifteen to twenty members, it cannot be the small group.
Small group of people may be friends or working partner in an organization. Small group can be best explained with the following scenario.
Tig, Shonice and Petra are best friends. Tig tells Shonice and Petra about a job interview that she had recently attended, when they are drinking coffee in the student union building. Then Shonice tells about her latest trip after returning home. Petra shares a story about her most recent rock-climbing adventure. This social group is described as a small group.