This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Liver disorders, Subject name: Pediatrics
Test to differentiate between neonatal hepatitis and biliary atresia in infant with jaundice: 
Select and explain. 
A. Gamma glutamyl transpeptidase, B. Alanine transaminase, C. Aspaate transaminase, D. Ultrasound
D: Ultrasound
Answer: D: Ultrasound 
Explanation: All the 3 hepatic enzymes are elevated in both neonatal hepatitis and biliary atresia. But USG may show triangular cord sign in biliary atresia.