Which cranial nerve is responsible for the sense of smell?

• A. Optic nerve
• B. Vestibulocochlear nerve
• C. Olfactory nerve
• D. Trigeminal nerve

Answer: (C)

Smell starts with sensors in the nasal lining that detect odor molecules. The signals from these olfactory receptor neurons travel along the olfactory nerve, which passes through the cribriform plate to reach the olfactory bulb. From there, the information is carried further to brain areas involved in odor perception, like the piriform cortex. This pathway is specific to smell, making the olfactory nerve the correct cranial nerve for this sense. By contrast, the optic nerve handles vision, the vestibulocochlear nerve handles hearing and balance, and the trigeminal nerve provides facial sensation and motor functions; those nerves do not carry the sense of smell.