Answer :
Answer:
Diffusion of responsibility.
Explanation:
Diffusion of responsibility is a sociopsychological phenomenon that occurs in a group of people which is sharing the responsibility of the outcome of particular actions or processes. It often occurs when it is not possible to identify who exactly is responsible for which elements of the outcome; when the outcome is subject to efforts from all participants of the process.
Here, both a teacher and a student are responsible for the quality of the outcome of the educational efforts. Meanwhile, when negative outcome (bed grade) occurs, each of them is psychologically prone to place responsibility on another and thus diffusion of responsibility takes place.