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': 'Apgar scores were 3, and 6 at 1 and 5 minutes. At 10 Apgar scores were 3, and 6 at 1 and 5 minutes. At 10 minutes child shows features of breathlessness,on CXR-mediastinal shift was there, possible causes – \na) Bilateral choanal atresiab) Pneumothoraxc) Congenital diaphragmatic herniad) Hyaline membrane disease \nSelect and explain. \nA. a, B. bc, C. ac, D. ad', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Congenital diaphragmatic hernia and pneumothorax cause respiratory distress with mediastinal shift to contralateral side.\nBilateral choanal atresia and HMD cause respiratory distress, but no mediastinal shift.', 'role': 'assistant'}]