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': 'Oxygen dissociation curve shifts to right in all except \nSelect and explain. \nA. Diabetic ketoacidosis, B. Blood transfusion, C. High altitude, D. Anaemia', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Hb-O2 dissociation curve shift to left indicates more affinity of Hb to O2, and thus less delivery of O2 to tissues. In stored blood, 2,3 DPG levels are decreased.\n\xa0\nShift to left seen in\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0 Increased pH\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0 Decreased 2,3 DPG, temperature, PCO2\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0 HbF (Fetal)\n\xa0\nShift to right seen in\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0 Decreased pH\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0 Increased 2,3DPG, temperature, PCO2\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0 HbS (Sickle cell)', 'role': 'assistant'}]