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
Which of the following is known as "Gateway of tears"? 
Select and explain. 
A. Killian's dehiscence, B. Rathke's pouch, C. Waldeyer's ring, D. Sinus of Morgagni
A: Killian's dehiscence
Answer: A: Killian's dehiscence 
Explanation: Inferior constrictor muscle has two pas: Thryopharygeus with oblique fibres Cricopharyngeus with transverse fibres Between these two pas exists a potential gap called Killian&;s Dehiscence also called "Gateway of tears" - As perforation can occur at this site during esophagectomy. (Ref: Textbook of diseases of ENT, PL Dhingra, 7th edition, pg no. 310)