This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
What is the diagnosis demonstrated in the barium esophagogram? 
Select and explain. 
A. Achalasia, B. Schatzki's ring, C. Nut cracker esophagus, D. Carcinoma esophagus
D: Carcinoma esophagus
Answer: D: Carcinoma esophagus 
Explanation: Barium oesophagram demonstrating advanced carcinoma with abrupt, irregular narrowing of the distal oesophagus, with more proximal dilation and an air-fluid level . ref - harrisons internal medicine 20e pg566,567