<prompt> Gas gangrene is caused by: March 2012Clostridium welchiiClostridium tetaniClostridium botulinumClostridium difficile  <response>: Ans: A i.e. Clostridium welchii Conditions and pathogens Established pathogens clostridium for gas gangrene group includes Cl. Perfringens welchii, Cl. septicum Cl. Novyi Established pathogen clostridium for tetnaus include Cl. Tetani Established pathogens clostridium for food poisoning group includes Cl. Perfringens type A gastroenteritis, Cl. Perfringens type C necrotising enteritis and Cl. Botulinum botulism Established pathogens clostridium for acute colitis include Cl. difficile 