This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology and breast, Subject name: Surgery
Where is bruit heard in thyroid gland 
Select and explain. 
A. Upper pole, B. Lower pole, C. Middle pole, D. Lateral side
A: Upper pole
Answer: A: Upper pole 
Explanation: Thrill is felt in the upper pole of the thyroid and also bruit on auscultation. It is because in the upper pole, superior thyroid aery enters the gland superficially and so thrill and bruit can easily be felt. In the lower pole inferior thyroid aery enters the gland from deeper plane and so thrill cannot be felt. Reference: SRB's Manual of Surgery, 6th Edition, page no = 463.