This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: miscellaneous, Subject name: Pathology
[{'content': 'Ratio of fat cells and RBC in bone marrow \nSelect and explain. \nA. 4:01, B. 1:01, C. 1:02, D. 2:01', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Bone marrow contains two types of stemcells: hemopoietic (which can produce blood cells) and stromal (which can produce fat, cailage and bone). ... Red blood cells, platelets and most white blood cells arise in red marrow; some white blood cells develop in yellow marrow', 'role': 'assistant'}]