This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Malabsorbtion Syndrome, Subject name: Medicine
[{'content': 'Xylose absorption test is used to assess: \nSelect and explain. \nA. Insulinoma, B. Atypical carcinoid, C. ZES, D. Monosaccharide absorption', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Condition Investigation of choice Insulinoma 72 hour prolonged fasting Atypical carcinoid 5 HTP ( hydroxyl tryptophan) ZES Secretin study Monosaccharide malabsorbtion D xylose absorption test', 'role': 'assistant'}]