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: Physiology
[{'content': 'The vasodilatation produced by carbon dioxide is maximum in one of the following: \nSelect and explain. \nA. Kidney, B. Brain., C. Liver., D. Hea.', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. BrainThe metabolic changes that produce vasodilatation, in most tissue, is decrease in O2 & pHT CO2 is associated with cutaneous & cerebral vosodilatationQ, but vasoconstriction elsewhere & usually a slow rise in BP.', 'role': 'assistant'}]