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 principle that in the spinal cord the dorsal roots are sensory and ventral roots are motor is known as: \nSelect and explain. \nA. Weber fechner law, B. Bell Magendie Law, C. Sensation law, D. Law of projection', 'role': 'user'}, {'content': "Answer: B \nExplanation: The principle that in the spinal cord the dorsal roots are sensory and ventral roots are motor is known as Bell Magendie law. Ref: Ganong's, Review of medical physiology, 21st Edition, Page 129.", 'role': 'assistant'}]