Answer:
Tie.
Step-by-step explanation:
In a social relationship strata, a tie refers to the connection one has with the friends or acquaintances of a friend. In other words, this form of relationship is formed with a mutual friend.
In the given condition, Janet knows Dr. Herring as a doctor-patient relationship whereas Janet and Sally are friends from school. So, the relationship of Janet, Sally, and Dr. Herring is what sociologists call a tie, where all individuals know each other but from different angles.