This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
[{'content': 'A person who subsisted on taking maize only for many years reported to a health facility with the signs of glossitis. His history suggested frequent attacks of diarrhea and memory loss. The likely condition is \nSelect and explain. \nA. Iron deficiency, B. Riboflavin deficiency, C. Beri Beri, D. Pellagra', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]