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': "All of the following are causes of microvesicular fatty liver except - \nSelect and explain. \nA. Reye's syndrome, B. Obesity, C. Acute fatty liver of pregnancy, D. Valproic acid", 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]