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': 'Potassium  is  maximally  absorbed  in which part of nephron? \nSelect and explain. \nA. Proximal convoluted tubules, B. DCT, C. Collecting ducts, D. Loop of Henle', 'role': 'user'}, {'content': 'Answer: A \nExplanation: POTASSIUM: REABSORPTION AND SECRETION\n•\xa0 K+ is the only electrolyte that is reabsorbed as well as secreted.\n•\xa0 65% of the K+\xa0is reabsorbed in PCT, 25% in loop and <10% reaches the distal nephron.\n•\xa0 Active\xa0reabsorption\xa0in\xa0PCT;\xa0secreted\xa0in\xa0DCT (Maximum\xa0 secretion).\xa0 K+ secretion\xa0is\xa0decreased when the amount of Na+\xa0reaching the DCT is small.\n•\xa0 K+\xa0secretion is also decreased when the H+\xa0secretion is increased.\n•\xa0 In DCT, Na+\xa0is reabsorbed and K+\xa0and H+\xa0compete for their secretion for the amount of Na +\xa0 reabsorbed.\n•\xa0 For\xa0K+\xa0and\xa0H+ , remember\xa0 the\xa0 terms\xa0 ‘hypokalemic alkalosis and hyperkalemic acidosis’', 'role': 'assistant'}]