This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thorax, Subject name: Anatomy
Constrictions in Esophagus by aoa is present at distance of from incisor 
Select and explain. 
A. 15 cm, B. 25cm, C. 30 cm, D. 40 cm
B: 25cm
Answer: B: 25cm 
Explanation: Construction of oesophagus at the following levels 15 cm-crossed by cricopharyngeus 22.5 cm-crossed by aoa 27.5 cm-crossed by left bronchus 37.5 cm-pierces the diaphragm All from incisor teeth BD CHAURASIA'S HUMAN ANATOMY VOL.1,PAGE NO 282