<prompt> A 30 yrs old female present with hearing loss and following audiogram is obtained. What is her most likely diagnosis?OtotoxicityNoise Induced Hearing LossOtosclerosisMenieres Disease  <response>: Wide AB gap conductive hearing loss on left side with carhas Notch dip at 2000Hz in Bone conduction indicates Otosclerosis PTA in Otosclerosis:1. Air conduction is poor worse for lower frequencies. 2. Large AB gap 3. Bone conduction is normal. 4. In some cases, there is a dip in bone conduction curve. 5. It is different at different frequencies but maximum at 2000 Hz and is called Carhas notch. Boilers notch is a similar dip in BC and AC curve but at 4000 Hz seen in noise induced hearing loss. 