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
Biological value of a protein is related to 
Select and explain. 
A. Nitrogen content, B. amino acid content, C. Sulphur content, D. Energy content
A: Nitrogen content
Answer: A: Nitrogen content 
Explanation: Ans) a (Nitrogen content) Ref paik 20th ed p 549Biological value of a protein is Retained N2 / Absorbed N2 x 100Protein efficiency ratio = Wt gain in gms / Gram of protein consumedNet protein utilization =Digestibility Coefficent x Biological value100 Aminoacid score =No of mg of one AA/gm of proteinNo of mg of same AA/gm of egg proteinx 100Quality of protein is assessed by comparison to the reference protein which is usually egg protein.