This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular system, Subject name: Physiology
[{'content': 'Bainbridge reflex is due to \nSelect and explain. \nA. Stretching of atria, B. Baroreceptor reflex, C. Decreased venous return, D. Increased ventricular activity', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ref:- Guyton and Hall Textbook of Medical Physiology 13th ed; pg num:- 268', 'role': 'assistant'}]