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
pH 7.24, PaO2 55 mm Hg, PaCO2 55 mm Hg, HCO3 - 30 mEq/L consistent with - 
Select and explain. 
A. Respiratory acidosis, B. Respiratory alkalosis, C. Metabolic acidosis, D. Metabolic alkalosis
A: Respiratory acidosis
Answer: A: Respiratory acidosis 
Explanation: None