Answer:
C) the bystander effect.
Step-by-step explanation:
Bystander effect: In psychology, the term bystander effect refers to the process in which an individual's tendency to help the other person in need is being inhibited due to the presence of the other person who can help.
A bystander is less likely to help a person in an emergency condition in the presence of another person as compared to the situation where the bystander is alone.
In the question above, Mr Hughes's reaction best illustrates the dynamic involved in the bystander effect.