This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nutrition, Subject name: Pediatrics
According to IAP classification of Grade IV malnutrition, Weight-for-age of the standard (%) is _________ 
Select and explain. 
A. 71-80, B. 61-70, C. 51-60, D. < 50
D: < 50
Answer: D: < 50 
Explanation: IAP classification of malnutrition Grade of malnutrition Weight-for-age of the standard (%) Normal >80 Grade I 71-80 (mild malnutrition) Grade II 61-70 (moderate malnutrition) Grade III 51-60 (severe malnutrition) Grade IV <50 (very severe malnutrition) Reference: Paediatrics; O.P Ghai; 8th edition; Page no: 97