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
The most likely diagnosis in a newborn who had a radiopaque shadow with an air-fluid level in the chest along with hemivertebrae of the 6th thoracic vertebra on plain X-ray is – 
Select and explain. 
A. Congenital diaphragmatic hernia, B. Oesophageal duplication cyst, C. Bronchogenic cyst, D. Staphylococcal pneumonia
B: Oesophageal duplication cyst
Answer: B: Oesophageal duplication cyst 
Explanation: Air-fluid level on the chest in a neonate with hemivertebrae suggests the diagnosis of esophageal duplication cyst.