This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hepatobiliary radiology, Subject name: Radiology
Investigation of choice for Acute cholecystitis is: 
Select and explain. 
A. H.I.D.A Scan, B. USG, C. CT Scan, D. Biopsy
B: USG
Answer: B: USG 
Explanation: IOC for Acute Cholecystitis: USG USG is the IOC for most GB pathologies Most Accurate Investigation for Acute Cholecystitis: H.I.D.A Scan (H.I.D.A is used for equivocal cases where USG is not conclusive ) IOC for Abdominal trauma :CECT