Question

Which of the following cranial nerves is responsible for the motor innervation of the muscles of mastication?

• A. Trigeminal nerve
• B. Facial nerve
• C. Glossopharyngeal nerve
• D. Hypoglossal nerve

Hint:

Remember: Trigeminal nerve (V) = sensory to face + motor to muscles of mastication.

Answer 1

The Correct Option is A

The muscles of mastication (masseter, temporalis, medial and lateral pterygoid) are innervated by the mandibular division (V3) of the trigeminal nerve (cranial nerve V). This branch carries motor fibers to these muscles, enabling chewing. The other options have different functions:
- Facial nerve (CN VII) supplies muscles of facial expression, not mastication.
- Glossopharyngeal nerve (CN IX) is involved in taste and swallowing.
- Hypoglossal nerve (CN XII) controls tongue movement.