This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Head and neck, Subject name: Anatomy
[{'content': 'True statement about left recurrent laryngeal nerve includes \nSelect and explain. \nA. It is a pure motor nerve, B. It supplies cricothyroid muscle, C. It arises from vagus as it crosses the first pa of subclan aery, D. It course through the groove between oesophagus', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The left recurrent laryngeal nerve arises in the superior mediastinum from the vagus nerve as it crosses the arch of aoa (lateral aspect).It hooks below the arch of aoa on the left side of ligamentum aeriosum behind the arch of aoa on its way to the tracheoesophageal groove.The recurrent laryngeal nerve provides motor innervation to all the intrinsic muscles of the larynx except the cricothyroid which is supplied by the external laryngeal nerve and sensory innervation to the mucous membrane of the laryngeal cavity upto the vocal cord.Each recurrent laryngeal nerve passes deep to the inferior constrictor muscle to enter the laryngeal cavity deep into the cricothyroid joint. Now it&;s called the inferior laryngeal nerve.Reference: Textbook of anatomy, Head neck and brainVishram Singh, 2nd edition, page no.348', 'role': 'assistant'}]