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': 'The important feature of 2,3 disphosphoglycerate includes \nSelect and explain. \nA. Higher concentration in adult blood, B. Contribution to Bohr effect, C. Increased affinity of O2 to haemoglobin, D. Associated with foetal blood to promote oxygenation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]