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: Surgery
[{'content': 'Villous adenoma presents as: September 2010 \nSelect and explain. \nA. Hypercalcemia, B. Hypokalemia, C. Hyperphosphaetemia, D. All of the above', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B: Hypokalemia Villous adenomas of the colon usually produce a hyperchloremic metabolic acidosis because of the loss of large volumes of colonic fluid, rich in potassium and bicarbonate. Occasionally, these tumors cause metabolic alkalosis. The mechanism is not well understood. Some authors opine that the hypokalemia caused by these tumors is the etiology of metabolic alkalosis.', 'role': 'assistant'}]