This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: FMGE 2019, Subject name: ENT
The muscle which is required to open Eustachian tube. 
Select and explain. 
A. Tensor veli palatini muscle, B. Salpingo pharyngeus, C. Tensor tympani, D. Levator veli palatini
A: Tensor veli palatini muscle
Answer: A: Tensor veli palatini muscle 
Explanation: Eustachian tube isclosed at rest&opens intermittentlyduring swallowing/yawning/sneezing. Opening of the tube The medial fibres of thetensor veli palatiniare attached to the lateral lamina of the tube and contract to open the tubal lumen. They are also calleddilator tubaemuscle. Accessory muscles for opening areLevator veli palatine & Salpingopharyngeus. Closure of the tube It is mainly due toelastic recoil of the cailageaided by the high degree of elastin on the roof. Ostmann's pad of fathelps to keep the tube closed.