This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Heart, Circulation, and Blood, Subject name: Physiology
[{'content': 'The main cause of increased blood How to exercising muscles is: \nSelect and explain. \nA. Raised blood pressure, B. Vasodilatation due to local metabolites, C. Increased sympathetic discharge to peripheral vessels, D. Increased heart rate', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (b) Vasodilatation due to local metabolites(Ref: Guyton, 13th ed/p.1093)In exercising muscle, there is accumulation of local metabolites leading to vasodilation - This increases blood flow.', 'role': 'assistant'}]