This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Radiology
Investigation of choice in obstructive jaundice is: 
Select and explain. 
A. ERCP, B. Ultrasound, C. Cholecystography, D. X-ray
B: Ultrasound
Answer: B: Ultrasound 
Explanation: Ans. Ultrasound