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: Surgery
[{'content': 'Which of the following is/are clinical features of tetanus? \nSelect and explain. \nA. Dysphagia, B. Risus sardonicus, C. Opisthotonus, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The clinical features of tetanus are: \n\nTrismus combined with pain and stiffness of neck, abdomen and back.\nDysphagia.\nAnxious expression (risus sardonicus).\nThe muscles of neck and trunk become rigid and the back is slightly arched (opisthotonus).\nRespiratory failure.', 'role': 'assistant'}]