A 60 year old man presents with fever watery diarrhea and crampyabdominal pain since one week.He has just completed treatment for osteomyelitis.Proctosigmoidoscopy reveals erythematous ulcerations andyellowish white plaques.The most likely diagnosis is:
a) Crohn’s disease
b) pseudomembranous colitis
c) Viral gastroenteritis
d) Clostridium perfringens enterocolitis