This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: FMGE 2018, Subject name: Medicine
[{'content': 'Gold standard method of diagnosing celiac disease is \nSelect and explain. \nA. Small bowel biopsy, B. Anti-endomysial antibodies, C. Blood picture, D. Biochemical test', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Best screening test: Anti TTG antibody Confirmatory / Gold standard: Small Bowel biopsy', 'role': 'assistant'}]