This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anatomy of Larynx, Subject name: ENT
Which of the following is not seen in Indirect Laryngoscopy: 
Select and explain. 
A. Base of tongue, B. Pyriform fossa, C. Posterior Commissure, D. Sub glottis
D: Sub glottis
Answer: D: Sub glottis 
Explanation: Hidden areas of larynx which are not seen on Indirect Laryngoscopy : Laryngeal Surface of epiglottis Ventricle Anterior commissure Subglottis Post Cricoid Area