<prompt> 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 isBile solubility testCatalase testOptochin sensitivityBacitracin sensitivity  <response>: 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. 