This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ear, Subject name: ENT
Acoustic reflex is lost in case of 
Select and explain. 
A. Stapedial palsy, B. Glomus tumour, C. Internal ear pathology, D. Malingering
A: Stapedial palsy
Answer: A: Stapedial palsy 
Explanation: ACOUSTIC REFLEX is the contraction of the stapedius muscle causing a change in impedance.The minimum sound intensity required to produce stapedial reflex is called stapedial reflex threshold(S). Reflexes are bilateral and can be measured on the ipsilateral and contralateral side. For ipsilateral the reflex is measured in the ear in which the tone is given while for contralateral the reflex is tested in the ear opposite to which the tone is given. Normally,the reflex occurs about 70-90 dB above the patient's threshold. ref:Hazarika 3rd edition,page no.63