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
Apex of lungs at what level of cervical veebra? 
Select and explain. 
A. C4, B. C5, C. C6, D. C7
D: C7
Answer: D: C7 
Explanation: The apex (apex pulmonis) is rounded, and extends into the root of the neck, reaching from 2.5 to 4 cm. above the level of the sternal end of the first rib. A sulcus produced by the subclan aery as it curves in front of the pleura runs upward and lateralward immediately below the apex. Ref: Anatomy of the Human Body Henry Gray.