Which statement best describes the optic nerve?

• A. It transmits auditory information to the brain
• B. It assists in regulating eye pressure
• C. It detects light directly
• D. It transmits visual information from the retina to the brain

Answer: (D)

The optic nerve’s job is to carry visual signals from the retina to the brain. Photoreceptors in the retina—rods and cones—detect light and convert it into electrical signals, and those signals travel along the retinal ganglion cell axons that form the optic nerve. It’s the highway for visual information, not a detector itself and not involved in regulating eye pressure. Auditory information is handled by the auditory nerve, and eye pressure is controlled by fluid dynamics inside the eye, not by this nerve. So the statement that it transmits visual information from the retina to the brain is the best description.