This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Larynx, Subject name: Anatomy
[{'content': 'Cricothyroid is supplied by: \nSelect and explain. \nA. External laryngeal nerve, B. Internal laryngeal nerve, C. Recurrent laryngeal nerve, D. Glossopharyngeal nerve', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. A. External laryngeal nerveThe cricothyroid muscle is the only tensor muscle of the larynx aiding with phonation. It attaches to the anterolateral aspect of the cricoid and the inferior cornu and lower lamina of the thyroid cartilage, and its action tilts the thyroid forward to help tense the vocal cords. This muscle is the only laryngeal muscle innervated by the superior laryngeal branch of the vagus nerve known as the external branch of the superior laryngeal nerve.', 'role': 'assistant'}]