This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Oral cavity & Oesophagus, Subject name: ENT
[{'content': 'Web constriction is seen in which pa of esophagus, in Plummer-Vinson syndrome \nSelect and explain. \nA. Thoracic, B. Abdominal, C. Cervical, D. Any of the above', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Predominantly, it affects females past 40 years. Barium swallow shows a web in the postcricoid region and the same can be seen on oesophagoscopy. (Ref: Textbook of diseases of ENT, PL Dhingra, 7th edition, pg no. 388)', 'role': 'assistant'}]