The olfactory nerve (CN I) is responsible for sense of smell; where does it exit the skull, and how is testing typically performed?

The olfactory nerve (CN I) is responsible for sense of smell; where does it exit the skull, and how is testing typically performed?

• A. Sense of smell; exits at the cribriform plate of the ethmoid bone; tested by presenting scents to each nostril; anosmia may indicate frontal lobe lesions.
• B. Sense of smell; exits at the foramen rotundum; tested by sniffing each nostril; anosmia indicates parietal lobe lesions.
• C. Sense of taste; exits at the foramen ovale; tested by tasting items; anosmia indicates brainstem lesions.
• D. Hearing; exits at the internal auditory meatus; tested by sound detection; anosmia indicates temporal lobe lesions.

Answer: (A)