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': 'The primary cause for the development of shock following hemorrhage is \nSelect and explain. \nA. Marked vasodilation, B. Decreased blood volume, C. Inadequate output by the hea, D. Obstruction to blood flow', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Hemorrhage is the most impoant cause of hypovolemic shock. There will be reduction in the venous return leading to a fall in cardiac output and BP. The severity of shock depends upon the rapidity of blood loss. Ref: Textbook of medical physiology by N Geetha, 3rd edition, page no. 204', 'role': 'assistant'}]