This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Medicine
[{'content': 'Acute exacerbation of COPD is done by all except \nSelect and explain. \nA. Pneumococcus, B. Moraxella catarrhalis, C. H influenza, D. Staph aureus', 'role': 'user'}, {'content': "Answer: D \nExplanation: Patients with COPD are frequently colonised with potential respiratory pathogens.Bacteria frequently implicated in COPD exacerbations include Streptococcus pneumoniae,Haemophilus influenzae, and Moraxella catarrhalis.In addition,Mycoplasma pneumoniae or Chlamydia pneumoniae are found in 5-10% of exacerbations. Harrison's medicine-18th edition,page no:2158.", 'role': 'assistant'}]