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
[{'content': 'Most impoant pathogen causing pneumonia in a patient with bronchiectasis is: \nSelect and explain. \nA. Streptococcus pneumoniae, B. Oral anaerobes, C. Acinetobacter spp, D. Staphylococcus aureus', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Impoant pathogen causing pneumonia in a patient with bronchiectasis 1. P. aeruginosa 2. Burkholderia cepacia 3. Staphylococcus aureus All others in the list are causing pneumonia in chronic alcoholic patients Ref: Harrison, E-18, P-2132.', 'role': 'assistant'}]