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': 'Mercury affects which pa of the kidney ? \nSelect and explain. \nA. PCT, B. DCT, C. Collecting duct, D. Loop of Henle', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., PCT", 'role': 'assistant'}]