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': 'All are true regarding capillaries except: \nSelect and explain. \nA. Have large total cross-sectional area, B. Contain larger quantity of blood than veins, C. Site of gaseous exchange, D. Lined by endothelium', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. Contains larger quantities of blood than veins', 'role': 'assistant'}]