This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (E.N.T.), Subject name: ENT
Most common organism causing both ASOM + CSOM includes 
Select and explain. 
A. Streptococcus pneumoniae, B. Staphylococcus, C. H. influenza, D. Moraxella
A: Streptococcus pneumoniae
Answer: A: Streptococcus pneumoniae 
Explanation: (A) Streptococcus pneumoniae # ASOM: Most common organisms in infants and young children are Streptococcus pneumonia (30%), Haemophilus influenzae (20%) and Morexella catarrhalis (12%). Other organisms include streptococcus pyogenes, staphylococcus aureus and sometimes pseudomas aeroginosa. In about 18-20%, no growth is seen. Many of the strains of H. influenzae and Morexella catarrhalis are /3-lactamase producing.> CSOM: Pus culture in both types of aerobic and anaerobic CSOM may show multiple organisms. Common aerobic organisms are PS aeruginosa, Proteus, Esch. coli & Staph, aureus, while anaerobes include Bacteroides fragilis and anaerobic streptococci.