This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Haematology, Subject name: Medicine
[{'content': '1722. A patient presents with macroglossia and atrophy of tongue papilla. His Hb Is 11.5 and MCV is 100. What should be the next step in Investigating this patient ? \nSelect and explain. \nA. B12 estimation, B. Brush biopsy of the lesion, C. Fluconazole treatment, D. Incision biopsy', 'role': 'user'}, {'content': 'Answer: A \nExplanation: <p>Deficiency of vit B12 & folate presents with anemia(macrocytic megaloblastic anemia), glossitis(smooth,beefy,red tongue).Hb level will be below normal range & MCV wil be elevated.So this is a case of vit B 12 deficiency & next choice of investigation is serum Vit B12 assay. </p><p>Harsh mohan textbook of pathology sixth edition pg no 306</p>', 'role': 'assistant'}]