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': 'Maize are deficient in - \nSelect and explain. \nA. Typtophan, B. Threonine, C. Methionine, D. Leucine', 'role': 'user'}, {'content': "Answer: A \nExplanation: The proteins of maize are deficient in tryptophan and lysine. REF. PARK'S TEXTBOOK OF PREVENTIVE AND SOCIAL MEDICAL 21ST EDITION. PAGE NO-627", 'role': 'assistant'}]