This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Head and neck, Subject name: Anatomy
[{'content': 'Isthmus of thyroid gland lies against following tracheal rings \nSelect and explain. \nA. 4-Feb, B. 3-Feb, C. 5-Feb, D. 3-Jan', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The thyroid gland lies against veebrae C5, C6, C7 and T1 embracing the upper pa of the trachea Each lobe extends from the middle of thyroid cailage to the fouh to fifth tracheal ring The isthmus extends from the second to fouh tracheal ring. Ref BDC volume 3,Sixth edition pg 141', 'role': 'assistant'}]