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
[{'content': "'Egg on Side' Appearance is seen in: \nSelect and explain. \nA. Tricuspid Atresia, B. Tetralogy of fallot, C. Total Anomalous Pulmonary Venous Connection (TAPVC), D. Transposition of great aeries", 'role': 'user'}, {'content': 'Answer: D \nExplanation: Chest Xray in a case of transposition of great aeries shows 1) appearance of an egg on its side because the aoa and pulmonary aery shadows are overlapping producing a narrow pedicle 2)Concave pulmonary aery segment, although vascularity in the lungs is increased unless transposition is associated with pulmonary stenosis. Ref: The Great Ormond Street Colour Handbook of Paediatrics and Child Health By Stephan Strobel, Peter Smith, Page 127; The Chest X-Ray By Francis Burgener, Mati Kormano, Page 16, 23; Pediatric Cardiovascular Medicine By James H. Moller, Page 479', 'role': 'assistant'}]