Surgical markings for finding the facial nerve is are-

After getting feedback on this question, we have changed answer from A => D. If you think A is the only correct answer let us know. Ans. is 'a' i.e., Tympano-mastoid suture o Surgical landmarks to identify main trunk of the facial nerve are as follows:Tympano mastoid suture line - it is located between the mastoid and the tympanic bones. The main facial trunk lies 6 -8 mm distal to the end of the suture.Tragal pointer - the main nerve trunk lies 1[?]0 to 1[?]5 cm deep and slightly anterior and inferior to the tip of the external ear canal cartilage.Posterior belly of digastric -the main nerve trunk lies 1 cm deep to the medial attachment of the posterior belly of digastric muscle to the digastric groove (mastoid notch) of the mastoid bone.Mastoid bone - main nerve trunk is identified inside the mastoid bone by mastoidectomy.