This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteria, Subject name: Microbiology
[{'content': 'A 45 years female complains of lower abdominal pain and vaginal discharge. On examination there is cervicitis along with a mucopurulent cervical discharge. The gram smear of the discharge shows presence of abundant pus cells but no bacteria. The best approach to isolates the possible causative agent would be: \nSelect and explain. \nA. Culture on chocolate agar supplemented with Haemin, B. Culture on McCoy cells, C. Culture on a bilayer human blood agar, D. Culture on vero cell lines', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Culture on McCoy cellsRef: Harrison, 19th/e, p. 1165 and Ananthanarayan, 9th/e, p. 415Chlamydiae are usually grown on McCoy cell line and HeLa cell line.Genital chlamydiasis is suspected if gram stained smear of urogenital exudates shows significant number of neutrophils. > 4/oil immersion field in urethritis, > 30 in cervicitis in the absence of gonococcal bacteria.", 'role': 'assistant'}]