This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory System Pa 2, Subject name: Physiology
[{'content': 'Of the total oxygen consumed by the body (per min.), greatest fraction is consumed by: \nSelect and explain. \nA. Liver, B. Brain, C. Muscle, D. kidney', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Under resting conditions, total O2 consumption by the body = 250 ml/min. Greatest fraction of this O2 consumption is by the liver Liver - 30% or 75 ml/min. Muscle consumes 20% or 50 ml/min. Brain consumes 18% or 45 ml/min. In terms of per 100 gm of tissue per min., highest O2 consumption is by the hea - 8 ml/100 gm/min.', 'role': 'assistant'}]