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: Forensic Medicine
[{'content': 'Respiratory depression is caused by A/E - \nSelect and explain. \nA. Opium, B. Barbiturate, C. Strychnine, D. Gelsemine', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Strychnine causes respiratory stimulation.\nOther three options can cause respiratory depression', 'role': 'assistant'}]