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
Regarding stapedial reflex, which of the following is true - 
Select and explain. 
A. It helps to enhance the sound conduction in middle ear, B. It is a protective reflex against loud sound, C. It helps in masking the sound waves, D. It is unilateral reflex
B: It is a protective reflex against loud sound
Answer: B: It is a protective reflex against loud sound 
Explanation: Stapedius muscle helps to dampen very loud sound and thus prevents noise trauma to the inner ear. It is supplied by VII nerve (facial nerve). Lesions of facial nerve lead to loss of stapedial reflex and hyperacusis or phonophobia i.e. intolerance to loud sounds.
For more details see chapter – physiology of hearing and assessment of hearing loss of the guide
NOTE:
Stapedial reflex = Acoustic reflex