Which of the following muscles is innervated by a branch of the posterior division of the mandibular nerve (CN V3)?

Question

A. masseter, B. medial pterygoid, C. mylohyoid, D. temporalis, E. stylohyoid

Answer 1

The mandibular nerve innervates muscles derived from the 1st pharyngeal arch which includes the muscles of mastication (medial pterygoid, lateral pterygoid, masseter and temporalis), the mylohyoid, tensor veli palatini, tensor tympani and the anterior belly of the digastric (the posterior portion is innervated by the facial nerve).

Which means what about the stylohyoid? This is innervated by the facial nerve.

Both the posterior belly of the digastric and stylohyoid are derived from the 2nd pharyngeal arch. Remembering what muscles are formed from which arch will help you in remembering nerve innervations and blood supply. I hope this helps!