This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Benign Gastric Disease, Subject name: Surgery
[{'content': 'Hypertrophic pyloric stenosis is best diagnosed by - \nSelect and explain. \nA. USG, B. CT SCAN, C. X-ray abdo supine, D. MRI', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., USG Hypertophic pyloric stenosiso Most common cause of nonbilious vomiting is Hypertrophic pyloric stenosis,o Male > female.o Vomiting starts with 3 week of age.o Palpable mass is seen in epigastric region,o Visible peristalsis is seen soon after feeding,o Confirmed by USG abdomen,o Contrast study show's :Shoulder signDouble tract sign.o Treatment surgery = Ramstedt procedure.", 'role': 'assistant'}]