This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Parasitology, Subject name: Microbiology
[{'content': 'A patient presents with lower gastrointestinal bleed. Sigmoidoscopy shows ulcer in the sigmoid. Biopsy from this area shows flask-shaped ulcers. Which of the following is the most appropriate treatment? \nSelect and explain. \nA. Intravenous ceftriaxone, B. Intravenous metronidazole, C. Intravenous steroids and sulphasalazine, D. Hydrocortisone enemas', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Intravenous metronidazole(Ref: Harrison, 18th/e, p. 1686; 17th/e, p. 1278)* Flask-shaped ulcer in a patient of GI bleed suggests amoebiasis (amoebic dysentery).* Metronidazole or Tinidazole are the DOCs.", 'role': 'assistant'}]