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': 'Corynebacterium diphtheriae can be grown within 6-8 hours on: \nSelect and explain. \nA. Potassium tellurite media with iron, B. McConkey’s agar, C. Dorset egg medium, D. Loeffler’s serum slope', 'role': 'user'}, {'content': 'Answer: D \nExplanation: On Loeffler’s serum slope, C. diphtheriae grows after 4–6 hours at 37°C producing small, circular, and white opaque colonies.\xa0\nIf no colonies are seen, the medium is reincubated further for 24 hours.\n\nParija SC. Textbook of Microbiology & Immunology. Elsevier Health Sciences; 2014. Page:218', 'role': 'assistant'}]