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': 'Blood cells arise in bone marrow and are subject to \nSelect and explain. \nA. Irregular renewal, B. Regular renewal, C. Infrequent renewal, D. None of the above', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]