<prompt> Most common cause of acute otitis media?H. influenzaStrep. PneumoniaeStaph aureusPseudomonas  <response>: The most common causative organism is Streptococcus pneumonia. Other common organisms are H. influenza and Moraxella catarrhalis. Less common causative organisms are streptococcus pyogenes, staphylococcus aureus and E.coli.Ref: PL Dhingra, Diseases of Ear, Nose Throat, 7th edition, pg no. 67 - 68 