A young woman being treated for serious burns develops severe diarrhea accompanied by intense abdominal pain. She passes several watery, foul-smelling, bloody stools a day. A colonoscopy reveals patches of yellowish lesions in the large intestine. The probable causative agent is
A) Giardia intestinalis. B) Clostridium difficile. C) Campylobacter. D) Salmonella enterica serotype Typhi. E) Vibrio cholerae.