This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Physiology
[{'content': 'Free water clearance by the kidney is increased by which of the following? \nSelect and explain. \nA. Diabetes insipidus, B. Renal failure, C. Diuretic therapy, D. Diabetes mellitus', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Free water clearance is the amount of water excreted in excess of that required to make the urine isotonic to plasma.', 'role': 'assistant'}]