This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anatomy
[{'content': 'Platysma is supplied by? \nSelect and explain. \nA. Cervical branch of facial nerve, B. Cervical branch of accessory nerve, C. Ansa cervicalis, D. Mandibular nerve', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]