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: Anatomy
Esophagus starts at which level - 
Select and explain. 
A. Upper border of cricoid cartilage, B. Lower border of cricoid cartilage, C. Thyroid cartilage, D. Hyoid cartilage
B: Lower border of cricoid cartilage
Answer: B: Lower border of cricoid cartilage 
Explanation: At the lower end of pharynx, at the level of lower border of cricoid cartilage, esophagus begins.