<prompt> 2nd constriction of esophagus is due to -Left principal bronchusArch of arortaPharyngoesophageal junctionNone  <response>: Ans. is b i.e., Arch of arorta Esophageal constrictionsNumberDistance from incisorBony levelAnatomical landmark1st2nd3rd4th15 cm 6 inches22-5 cm 9 inches27-5 cm 11 inches37 -5 -40 cm 15-16 inchesC6T4T6T10At its beginning pharyngoesophageal junctionCrossing of aortic archCrossing of left main bronchusPiercing diaphragm at lower esophageal sphinctor 