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
Reference protein is - 
Select and explain. 
A. Egg, B. Fish, C. Milk, D. Meat
A: Egg
Answer: A: Egg 
Explanation: Egg contains all nutrients except vitamin C.it has all the nine essential amino acids needed by the body in right propoion and net protein utilisation is 100.REF.PARK'S TEXTBOOK OF PREVENTIVE AND SOCIAL MEDICINE.Editon-21.Page no.-582