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': 'Which of these is not a cause of rightward shift of Oxygen – Hemoglobin dissociation curve? \nSelect and explain. \nA. Increased hydrogen ions, B. Decreased CO2, C. Increased temperature, D. Increased BPG', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Hb-O2\xa0dissociation curve shift to left indicates more affinity of Hb to O2 and thus less delivery of O2\xa0to tissues. Exercise causes increased 2,3 DPG.\nShift to left seen in\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0Increased pH\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0Decreased 2,3 DPG, temperature, PCO2\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0HbF (Fetal)\nShift to right seen in\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0Decreased pH\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0Increased 2,3DPG, temperature, PCO2\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0HbS (Sickle cell)', 'role': 'assistant'}]