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': 'During exercise increase in 02 delivery to muscles is because of all except : \nSelect and explain. \nA. Oxygen dissociation curve shifts to left, B. Increased stroke volume, C. Increased extraction of oxygen from the blood, D. Increased blood flow to muscles', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e. Oxygen dissociation curve shifts to left', 'role': 'assistant'}]