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: Medicine
[{'content': 'A patient presents with a cavitatory lesion in right upper lobe of lung. The best investigation is? \nSelect and explain. \nA. Branchoscopy, lavage and brushing, B. C.T. Scan, C. X ray, D. FNAC', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Answer is A (Bronchoscopy, lavage and brushing) : The basic idea is to obtain a tissue biopsy. FNAC could he used, however it would ceainly not be the best. Bronchoscopy would allow, both, direct visualization and biopsy, and so is the best option here.', 'role': 'assistant'}]