This question is missing the options. I've found the complete question online. It is as follows:
Leo drops his stack of books in the library. They scatter everywhere, and it's a mess. People all around see the mess, but nobody goes over to help immediately. Then finally, one girl goes over to help him. Which term describes how people looked on but didn't offer to help Leo out immediately?
a) bystander effect
b) diffusion of responsibility
c) social facilitation
d) conformity
Answer:
The term that describes how people looked on but didn't offer to help out immediately is letter a) bystander effect.
Step-by-step explanation:
The bystander effect can be observed when several people see something happen to someone and do not react in order to help, even if it is an emergency.
The bystander effect was popularized by social psychologists Bibb Latané and John Darley after a woman was stabbed to death in front of her apartment in New York. None of her neighbors tried to intervene and help. One explanation to such inertia is that people observe those around them to decide how to act. If no one is helping, they choose not to help as well.