Which cranial nerve is responsible for sensation in the nasal cavity?

The trigeminal nerve (CN V) is responsible for sensation in the nasal cavity, as it is the main sensory nerve of the face. It has three major branches: the ophthalmic, maxillary, and mandibular nerves. The ophthalmic branch, in particular, is responsible for sensation in the upper part of the face, including areas such as the nasal cavity.

This nerve is crucial for detecting various sensations, including pain, temperature, and touch within the nasal passages. Given the significant role of the trigeminal nerve in conveying sensory information from the nasal mucosa to the brain, it is the correct answer to this question. Understanding the specific functions of cranial nerves is important for recognizing how sensory pathways operate in areas like the nasal cavity.