This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
[{'content': 'Radiological features of left ventricular hea failure are all, except- \nSelect and explain. \nA. KerlyB lines, B. Cardiomegaly, C. Oligemic lung fields, D. peribronchial cuffing', 'role': 'user'}, {'content': 'Answer: C \nExplanation: In chest radiography, the Westermark sign is a sign that represents a focus of oligemia (hypovolemia) (leading to collapse of vessel) seen distal to a pulmonary embolism (PE). While the chest x-ray is normal in the majority of PE cases, the Westermark sign is seen in 2% of patients. Ref Davidson 23rd edition pg 460', 'role': 'assistant'}]