What is an unreliable narrator? What makes him/her unreliable?

Which phrase from "the pedestrian" convey bradbury's message that a tv-obsessed world is a place where people are disconnected from one another and reality? o a. the headlights of the police car made leonard mead feel like a museum specimen, needle thrust through chest." o b. leonard mead noticed that the cold air "cut the nose and made the lungs blaze like a christmas tree inside." o c. leonard mead "listened to the faint push of his soft shoes through autumn leaves with satisfaction." o d. people who watched tv felt "the gray or multicolored lights touching their faces, but never really touching them."