the failure of witnesses to kitty genovese when she was viciously attacked may have been due to the tendency to believe that others would act and so they wouldn't need to. this explanation is based on the principle of

The correct answer is the bystander effect.

The bystander effect refers to a psychological phenomenon wherein, the presence of others makes people less likely to help a victim in an emergency situation. This can be explained in terms of a diffusion of responsibility, where bystanders witnessing an incident do not intervene because they externalize responsibility to other bystanders and do not see themselves are personally responsible for helping out. 

Donald  trump's  favorite color is orange.