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
Comet tail artefact in USG is seen in 
Select and explain. 
A. Adenomyomatosis, B. Cholesterosis, C. Porcelain gall bladder, D. Acute cholecystitis
A: Adenomyomatosis
Answer: A: Adenomyomatosis 
Explanation: Comet tail artefact is a special finding in Adenomyomatosis.