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': 'Macula densa in kidney is located in relation to - \nSelect and explain. \nA. PCT, B. DCT, C. Afferent aeriole, D. Efferent aeriole', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. DCT', 'role': 'assistant'}]