Answer :
Social psychologists have arranged for people to drop coins or pencils in elevators in order to study the bystander effect.
The more people there are, the less likely it is that someone in need of assistance would receive it. This phenomenon is known as the "bystander effect." The bystander effect states that when an emergency situation arises, witnesses are more inclined to respond if there are few or no other witnesses. The bystander effect is primarily caused by two things.
First, there is a diffusion of responsibility when other people are present. The requirement for proper and socially acceptable behaviour serves as the second justification. People frequently interpret the inaction of other observers as a sign that their own response is neither necessary nor appropriate.
The correct answer is option A.
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