This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Physiology
[{'content': 'Which of the following will lead to pulmonary vasodilation? \nSelect and explain. \nA. Hypercapnia, B. Decreased PaCO2, C. Baroreceptor stimulation, D. Chemoreceptor stimulation', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Baroreceptors are mechanoreceptors located in the carotid sinus and in the aoic arch. Their function is to sense pressure changes by responding to change in the tension of the aerial wall. The baroreflex mechanism is a fast response to changes in blood pressure Ref: guyton and hall textbook of medical physiology 12 edition page number:364,365,366', 'role': 'assistant'}]