<prompt> In a school child had abscess on lower leg. Swab taken revealed gram positive beta-hemolytic streptococci, and these were bacitracin sensitive. School physian observed that similar organism was isolated from throats of many other children. Which of the following is true statement with ragards to this patient -Difference in surface protein can differentiate the pathogenic bacteria from the pharyngeal culture bacteria.Component C carbohydrate can differentiate the pathogenic bacteria from the throat culture bacteriaMEG 3 positive are throat culture streptococciDepending on M protein the cutaneous pathogenic bacteria can be differentiated from the pharyngeal culture bacteria  <response>: Ans. is d i.e., Depending on M protein the cutaneous pathogenicbacteria can be differentiated from the pharyngeal culture bacteria Bacitracin sensitive gram positive beta hemolytic cocci is streptococcus pyogenes. Two most common sites of infection with streptococci are the upper respiratory tract pharyngitis, tonsilitis and the skin impetigo. S. pyogenes causing skin infection impetigo tend to belong to different M serotypes than those associated with respiratory infection pharyngitis. The M protein types of a S. pyogenes most commonly associated with skin infection impetigo are different from those causing resporatory infection Pharyngitis 