This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anatomy of Larynx, Subject name: ENT
External laryngeal nerve supplies which muscle? 
Select and explain. 
A. Cricothyroid, B. Thyroarytenoid, C. Cricoarytenoid, D. Vocalis
A: Cricothyroid
Answer: A: Cricothyroid 
Explanation: ANSWER: (A) Cricothyroid REF: Dhingra's 4" ed p. 318* Superior laryngeal nerve: arises from the inferior ganglion of the vagus* Divides into external and internal branches.* External laryngeal nerve supplies cricothyroid* Internal laryngeal nerve pierces the thyrohyoid membrane and gives sensory supply to larynx and hypopharynx.