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': 'How much blood flows to skeletal muscles during exercise? \nSelect and explain. \nA. 50 to 75 mL/min of blood per 100 g of muscle, B. 4 to 7 mL/min of blood per 100 g of muscle, C. 20 to 30 mL/min of blood per 100 g of muscle, D. 10 to 20 mL/min of blood per 100 g of muscle', 'role': 'user'}, {'content': "Answer: A \nExplanation: Blood flow to tissues is generally propoional to metabolic activity. At rest, approximately 20% of CO is distributed to the skeletal muscle. However, during physical activity, the majority (85%) of the increased CO is diveed to the working muscles. This represents an increase from 4 to 7 to 50 to 75 mL/min of blood per 100 g of muscle. Ref: Fletcher G.F., Flipse T.R., Safford R.E. (2011). Chapter 100. Exercise in Health and Cardiovascular Disease. In V. Fuster, R.A. Walsh, R.A. Harrington (Eds), Hurst's The Hea, 13e.", 'role': 'assistant'}]