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: ENT
Which of the following part is NOT included in hypopharynx - 
Select and explain. 
A. Pyriform sinus, B. Postcricoid region, C. Anterior pharyngeal wall, D. Posterior pharyngeal wall
C: Anterior pharyngeal wall
Answer: C: Anterior pharyngeal wall 
Explanation: Clinically, hypopharynx is subdivided into three regions:-


The pyriform sinus
Post-cricoid region
The posterior pharyngeal wall