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
Cerelas are deficient in? 
Select and explain. 
A. Alanine, B. Lysine, C. Methionine, D. Cysteine
B: Lysine
Answer: B: Lysine 
Explanation: 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