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': 'Life span of neutrophils is: \nSelect and explain. \nA. 6 hours, B. 6 days, C. 10 days, D. 15 days', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e. 6 HoursThe average half life of neutrophils in the circulation is 6 Hours.QTo maintain normal circulating blood level, production of 100 billion neutrophils /day is necessary. Half life of transfused platelet is 4 daysQ', 'role': 'assistant'}]