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': 'A patient presents with a solitary pulmonary nodule (SPN) on X-ray. The best investigation to come to diagnosis would be – \nSelect and explain. \nA. MRI, B. CT Scan, C. USG, D. Image guided biopsy', 'role': 'user'}, {'content': 'Answer: D \nExplanation: "Thoracotomy with resection represents the most direct and definitive means of diagnosis (and treatment) of\xa0solitary pulmonary nodule"."Thoracotomy is the most definitive method for determining the diagnosis in patients with SNPs".\n\nHowever, a thoracotomy is associated with significant morbidity, complications and mortality. Therefore, CT guided a transthoracic biopsy is the invasive diagnostic procedure of choice.\n\nNote -If the question would have been about the next investigation of choice (instead of best investigation), then the answer will be CT scan.', 'role': 'assistant'}]