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: Surgery
Commonest site of esophagus carcinoma is - 
Select and explain. 
A. Upper 2/3, B. Middle 1/3, C. Lower 1/3, D. Crico-esophageal junction
B: Middle 1/3
Answer: B: Middle 1/3 
Explanation: Ans. is ' b ' i.e. Middle 113