<prompt> A 5-year-old unimmunized child presented with sore throat swelling of neck. On examination of throat, the following was seen. What is the most probable causative organism?Streptococcus pyogenesMycobacterium tuberculosisStaphylococcus aureusCorynebacterium diphtheriae  <response>: d. Corynebacterium diphtheriaeA membrane is seen over the tonsil in this child with swelling of neck. Demonstration of bacilli on Albert staining, in the given scenario is suggestive of Diphtheria 