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': 'Nerve ending sensitive to noxious stimuli are present in all excepta) Stomachb) Intestinec) Mesentryd) Livere)  Brain \nSelect and explain. \nA. ab, B. de, C. cd, D. bd', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Brain does not have any pain receptors, while lung and liver parenchyma are insensitive to pain.', 'role': 'assistant'}]