Which structure carries visual signals to the brain?

• A. Optic nerve
• B. External auditory canal
• C. Cochlea
• D. Semicircular canals

Answer: (A)

Visual signals travel from the retina to the brain via the optic nerve. The retina converts light into electrical impulses, and those impulses are carried out of the eye by a bundle of retinal ganglion cell axons that forms the optic nerve. From there, the information is relayed onward to the brain for processing, ultimately reaching the visual cortex in the occipital lobe. The other structures have different roles: the external auditory canal channels sound to the eardrum, the cochlea turns those vibrations into neural signals for hearing, and the semicircular canals detect head movement for balance. So, the optic nerve is the pathway specifically responsible for carrying visual information to the brain.