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: Psychiatry
[{'content': 'Post Traumatic stress syndrome is due to \nSelect and explain. \nA. Head Injury, B. CVD, C. Minor Stress, D. Major Life threatening events', 'role': 'user'}, {'content': 'Answer: D \nExplanation: D i.e. Major life threatening events', 'role': 'assistant'}]