This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: ABG Analysis Simplified, Subject name: Medicine
[{'content': 'A 68 year old man with a history of very severe COPD (FEV1~1.0L, <25% predicted) presents to the ER complaining of worsening dyspnea and an increase in the frequency and purulence of his sputum production over the past 2 days. His oxygen saturation is 78% on room air. Before he is placed on supplemental oxygen, a room air aerial blood gas is drawn and reveals: pH 7.25, PCO2 - 68, PO2 - 48, HCO3 -31. What is the diagnosis? \nSelect and explain. \nA. Respiratory acidosis uncompensated, B. Respiratory acidosis paially compensated, C. Metabolic acidosis uncompensated, D. Metabolic alkalosis paially compensated', 'role': 'user'}, {'content': 'Answer: B \nExplanation: pH- 7.25 (acidic) PCO2 - 68 mm Hg (respiratory acidosis) HCO3 - 31 mm Hg (elevated) - but pH acidic - So paially compensated', 'role': 'assistant'}]