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': 'Rubor in inflammation is due to - \nSelect and explain. \nA. Dilation of aerioles, B. Increased vascular permeability, C. Increased viscocity of blood, D. Edema', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Dilation of aerioles", 'role': 'assistant'}]