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
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.
>Bile solubility test
>Catalase test
>Optochin sensitivity
>Bacitracin sensitivity