This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
[{'content': 'Pachydermia laryngitis - M/C site of involvement \nSelect and explain. \nA. Vestibular fold, B. Arytenoid cailage, C. Anterior 1/3 commissure, D. Posterior 1/3 and anterior 1/3 commissure', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Pachyderma laryngitis affects the medial surface of arytenoid cailage, in paicular the vocal processes. Ref:- Scott&;s Brown 7th edition; pg num:- 2196', 'role': 'assistant'}]