This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pharynx, larynx and trachea and cranial nerves 3,4,6, Subject name: Anatomy
A 10 year old child due to choked suddenly on consuming food . On the failed attempt of Valsalva's manoeuvre a needle cricothyrotomywas performed . It would open into which of the following regions? 
Select and explain. 
A. Rima glottidis, B. Laryngeal vestibule, C. Laryngeal ventricle, D. Infraglottic cavity
D: Infraglottic cavity
Answer: D: Infraglottic cavity 
Explanation: Infraglottic cavity extends from rima glottidis to the lower border of the cricoid cailage. The rima glottidis is the space between the vocal folds and arytenoid cailages. Vestibule extends from the laryngeal inlet to the vestibular folds. Ventricle extends between vestibular fold and the vocal fold. Piriform recess is a pear-shaped fossa in wall of the laryngopharynx lateral to the arytenoid cailage.