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': "A child come with fever, cold, cough, membrane over tonsils; nasal swab is taken, culture should be done on which medium for earliest diagnosis ? \nSelect and explain. \nA. Loffelers serum slop, B. L. J. media, C. MC Conkey's Agar, D. Citrate media", 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Loffelers serum slop Diphtheria bacilli grow on Loeffler's serum slope very rapidly and colonies can be seen in 6-8 hours, long before other bacteria grow.", 'role': 'assistant'}]