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: Medicine
Arterial blood gas analysis of a patient admitted to the medical emergency is as follows : pH = 7.2, HCO3 = 38 mmol/L, pCO2 = 56 mm Hg. This indicates : 
Select and explain. 
A. Metabolic acidosis, B. Metabolic acidosis with respiratory compensation, C. Respiratory acidosis, D. Respiratory acidosis with renal compensation
D: Respiratory acidosis with renal compensation
Answer: D: Respiratory acidosis with renal compensation 
Explanation: None