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': 'In a patient with severe central diabetes insipidus caused by a lack of anti\xaddiuretic hormone secretion, which part of  the  tubule  would  have  the  lowest tubular fluid osmolarity? \nSelect and explain. \nA. B, B. C, C. D, D. E', 'role': 'user'}, {'content': 'Answer: D \nExplanation: In the absence of ADH, the late distal tubule and CD are not permeable to water. Therefore, the\xa0 tubular ﬂuid, which is already dilute when it leaves the loop of Henle (about 100 mOsm/L), becomes\xa0 further diluted as it ﬂows through the late distal tubule and CD as electrolytes are reabsorbed.\nTherefore, the ﬁnal urine osmolarity in the complete absence of ADH is less than 100\xa0 mOsm/L.', 'role': 'assistant'}]