This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gastrointestinal tract, Subject name: Pharmacology
[{'content': "Which one of the drugs is useful in treating Crohn's disease? \nSelect and explain. \nA. Infliximab, B. Azathioprine, C. Tacrolimus, D. Cyclosporine", 'role': 'user'}, {'content': 'Answer: A \nExplanation: drug used in CrD are a)5ASA compound b)coicosteroid c)immuno suppressent d)TNalpha inhibitors(infliximab) ESSENTIALS OF MEDICAL PHARMACOLOGY SEVENTH EDITION KD TRIPATHI PG NO.683,685', 'role': 'assistant'}]