This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
Which of the following is not true regarding pseudomembranous  colitis? 
Select and explain. 
A. Antibiotic associated diarrhea eg: 3rd gen cephalosporins ., B. Characterised by pseudomembranes at the site of mucosa injury., C. Presents as watery diarrhea, abdominal pain and fever, D. Clostridium difficile is the only cause.
D: Clostridium difficile is the only cause.
Answer: D: Clostridium difficile is the only cause. 
Explanation: Though pseudomembranous colitis is clasically caused by clostridium difficile, but also caused by salmonella, clostridium perfringes and saurevs in some cases.