This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cranial Nerves, Subject name: Anatomy
[{'content': '50-year-old man presents to the speech therapist complaining of dryness of the mouth. The therapist performs a swallowing study and, on examination, finds that the man has a lack of salivary secretion from the submandibular gland. This indicates a lesion of which of the following nervous structures? \nSelect and explain. \nA. Lingual nerve at its origin, B. Lesser petrosal nerve, C. Superior cervical ganglion, D. Chorda tympani in the middle ear cavity', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Chorda tympani nerve contains preganglionic parasympathetic fibres responsible for secretion of the submandibular gland. Lingual nerve at its origin is not yet joined by the chorda tympani. Superior cervical ganglion provides sympathetic fibres, which supply blood vessels in the submandibular gland. Lesser petrosal nerve contains preganglionic parasympathetic fibres that synapse in the otic ganglion. Auriculotemporal nerve contains postganglionic parasympathetic fibres, which are responsible for secretion of the parotid gland.', 'role': 'assistant'}]