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
Which of the following is the least common bacteria responsible for Acute Exacerbation of Chronic Bronchitis 
Select and explain. 
A. Streptococcus pneumoniae, B. Moraxella catarrhalis, C. Haemophilus influenza, D. Staphylocccus aureus
D: Staphylocccus aureus
Answer: D: Staphylocccus aureus 
Explanation: Ans. is 'd' i.e., Staphylocccus aureus Most common bacterias associated with acute excerbation in COPD Hemophilus influenzae Moraxella catarrhalis Streptococcus pneumoniae