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: Medicine
[{'content': 'In idiopathic polymyositis, following are seen except-a) Ocular muscles commonly involvedb) Pharyngeal muscles involvedc) Cutaneous manifestationsd) Proximal limb muscles invariably involved \nSelect and explain. \nA. a, B. bc, C. ac, D. b', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]