<prompt> The main causative organism of Gas gangrene isBacillus anthraxCloastridium tetaniClostridium defficileClostridium perfringens  <response>: Gas gangrene is caused by Clostridium PerfringensRef: Harrison;s Principles of Internal Medicine; 19th edition; Chapter 156; Infections of the Skin, Muscles, and Soft Tissues 