This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular Radiology, Subject name: Radiology
[{'content': 'Which of the following is not a Chest radiographic feature of Left atrial enlargement? \nSelect and explain. \nA. Double Left hea border, B. Elevated Left main bronchus, C. Splaying of carina, D. Enlargement of Left atrial appendage', 'role': 'user'}, {'content': 'Answer: A \nExplanation: * Left atrial enlargement / Mitral stenosis: Features: * Straighten of left hea borders * Widening of carina with elevated left main bronchus * Has double right hea borders * Enlargement of left atrial appendage * Indentation of oesophagus', 'role': 'assistant'}]