This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Medicine
[{'content': 'Choose the best Lab value for a patient with central diabetes insipidus- Urinary Osmolality & Serum Osmolality \nSelect and explain. \nA. 50 300, B. 500 260, C. 50 260, D. 500 100', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans is option 1 Urinary osmolality 50 and serum osmolality 300 Diabetes insipidus is the reverse of SIADH, here the ADH level is decreased which leads to excessive water loss from the kidney resulting in hypeonic plasma associated with dilute urine. So best value is option a Ref Harrison 17/e p 2219 Nelson 16/e p2099, 1575', 'role': 'assistant'}]