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 had pustular lesion on leg. On grainstaining gram positive cocci are seen. To establish the diagnosis of Group A streptococcal erythroderma, the test used is \nSelect and explain. \nA. >Bile solubility test, B. >Catalase test, C. >Optochin sensitivity, D. >Bacitracin sensitivity', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Bacitracin sensitivity (Ref: Harrison 16thle p 741, Anantnatyan] Streptococcal erythroderma is caused by streptococcus pyogenus Streptococcus pyogenus is b hemolytic streptococci and is Bacitracin positive.', 'role': 'assistant'}]