<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:An 11-year-old boy is brought to the emergency department by his parents for confusion and fever. The patient began complaining of a headache yesterday afternoon that progressively got worse. After waking him up this morning, his mom noticed that he seemed funny and wasnt able to carry a conversation fully. When asked about his past medical history, the dad claims that hes been healthy except for 2-3 episodes of finger pain and swelling. Physical examination demonstrates a boy in moderate distress, altered mental status, and nuchal rigidity. A CSF culture reveals a gram-positive, diplococci bacteria. What characteristic would you expect in the organism most likely responsible for this patients symptoms?? A: Culture on chocolate agar with factors V and X, B: K-capsule, C: Maltose fermentation, D: Optochin sensitivity, E: Pyocyanin production,  <response>: Based on the clinical presentation of meningitis with fever, headache, altered mental status, and nuchal rigidity, the most likely organism is Streptococcus pneumoniae. The history of episodic finger pain and swelling suggests a predisposition for invasive pneumococcal disease. S. pneumoniae is a gram-positive diplococcus that commonly causes meningitis. To identify S. pneumoniae, we would expect the organism to demonstrate optochin sensitivity. Optochin ethylhydrocupreine hydrochloride is an antibiotic that is used to distinguish S. pneumoniae from other alpha-hemolytic streptococci. S. pneumoniae is optochin sensitive, meaning growth is inhibited in the presence of optochin. This characteristic can help identify S. pneumoniae as the causative organism.D: Optochin sensitivity 