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: Pathology
[{'content': 'The 4 classical features of inflammation are described by - \nSelect and explain. \nA. Celsus, B. Hippocrates, C. Aristotle, D. Galen', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Celsus", 'role': 'assistant'}]