This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
[{'content': 'Blood can be stored with CPD A for \nSelect and explain. \nA. 15 days, B. 21 days, C. 30 days, D. 45 days', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Blood can be stored for 21 days with CPD ( Citrate phosphate dextrose ) Blood can be stored upto 35 days with CPD A ( Citrate phosphate dextrose adenine )', 'role': 'assistant'}]