Final answer:
The parotid gland is supplied by the glossopharyngeal nerve, after the secretomotor fibers originating from the inferior salivary nucleus synapse in the otic ganglion.
Step-by-step explanation:
The parotid gland is primarily innervated by the glossopharyngeal nerve (Cranial nerve IX), and the related parasympathetic secretomotor fibers originate from the inferior salivary nucleus. These fibers project as preganglionic fibers and form a synapse in the otic ganglion, which then projects to the parotid gland to promote salivation. Therefore, the correct option for the supply of the parotid gland would be 'Inferior salivary nucleus → otic ganglion→ glossopharyngeal nerve'.