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 the following statement (s) is/are true about Hb–O2 dissociation curvea) Fetal Hb shifts curve to leftb) Hypothermia shifts curve to leftc) Hypercarbia shifts curve to leftd) Left shift cause more O2 release to tissue \nSelect and explain. \nA. ab, B. a, C. ad, D. bc', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Hb-O2 dissociation curve shift to left indicates more affinity of Hb to O2, and thus less delivery of O2 to tissues.\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'}]