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: Microbiology
[{'content': 'Sereny test is positive in - \nSelect and explain. \nA. Entero-invasive E.coli, B. Entero-pathogenic E.coli, C. Entero-toxigenic E.coli, D. Entero-aggregative E.coli', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Entero-invasive E. coliSereny test is done for EIEC and shigella.In this test, instillation of a suspension of freshly isolated ETEC or shigella into the eyes of guinea pigs leads to mucopurulent conjuctivitis and severe keratitis.", 'role': 'assistant'}]