This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nutrition and health, Subject name: Social & Preventive Medicine
[{'content': 'Cerelas are deficient in? \nSelect and explain. \nA. Alanine, B. Lysine, C. Methionine, D. Cysteine', 'role': 'user'}, {'content': "Answer: B \nExplanation: Cereal proteins are poor in nutritive value being deficient in the essential amino acid,lysine.REF.PARK'S TEXTBOOK OF PREVENTIVE AND SOCIAL MEDICINE.Editon-21.Page no.-578", 'role': 'assistant'}]