This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Diagnostic and operative ENT, Subject name: ENT
[{'content': 'Which of the following structures is not seen on bronchoscopy \nSelect and explain. \nA. Trachea, B. Vocal cords, C. Subcarinal lymph nodes, D. First segmental division of bronchi', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Bronchoscopy can be done as pa of an endobronchial ultrasound (EBUS) to look at the lymph nodes and other structures in the area between the lungs. ... If suspicious areas such as enlarged lymph nodes are seen, a hollow needle can be passed through the bronchoscope and guided into these areas to obtain a biopsy. Ref- Dhingra , 6th edition, pg no. 425.', 'role': 'assistant'}]