This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ear, Subject name: ENT
[{'content': 'Acute otitis media is most commonly caused by: \nSelect and explain. \nA. Streptococcus pneumoniae, B. Hemophilus influenzae, C. Staphylococcus aureus, D. Klebsiella pneumoniae', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. (a) Streptococcus pneumoniaRef: Dhingras ENT 6th ed./62* Acute otitis media is most commonly caused by Streptococcus Pneumonia. However it can also be caused by H.Influenzae and Moraxella catarrhalis.# Causative Agents:INFECTIONMC ORGANISMPerichondritisPseudomonasMalignant otitis externaPseudomonasLocalized otitis externaStaphylococcus AureusAcute suppurative otitis mediaStrep PneumoniaeChronic otitis MediaPseudomonas', 'role': 'assistant'}]