Which cranial nerve is responsible for vision?

• A. Olfactory
• B. Optic
• C. Oculomotor
• D. Trochlear

Answer: (B)

Vision relies on a nerve that carries sensory signals from the retina to the brain. This nerve, the optic nerve, is the second cranial nerve and serves as the main highway for visual information. When light hits the retina, photoreceptors convert it into electrical signals, which travel through the optic nerve to the brain, where they are processed in the visual cortex to produce sight. Along the way, some fibers cross at the optic chiasm and then proceed through the optic tract to the thalamus and onward to the visual cortex.

The other nerves listed have different roles: the olfactory nerve handles smell; the oculomotor nerve controls most eye movements and pupil constriction; the trochlear nerve moves the eye via the superior oblique muscle. Since vision is carried specifically by the optic nerve, it is the correct choice.