This question lacks options, options are: A. Petrous part B. Mastoid process C. Tympanic part D. Squamous part. The correct answer is D.
Explanation:
Squamous part represents most of the lateral surface of the temporal bone. It is located on the external acoustic meatus. Its surface is smooth on the outside and slightly convex on the inside wall. It is the area in contact with the parietal and has two portions, one vertical and the other a small horizontal portion, divided by the zygomatic process. The external face of the vertical portion is convex and smooth, presents a vascular groove with an upward and backward direction for the middle meningeal artery, and is covered by the temporal muscle. The horizontal crest, a rearward extension of the zygomatic process, is the mastoid crest or temporal line and indicates the level of the floor of the middle cranial fossa. This line is important because it will be the upper limit of the mastoidectomy. Above and slightly posterior to the EAC, a pointed process is observed, the suprathetic spine or Henle's spine and behind, the cribriform or supramathetic fossa. The inner face of the vertical portion of the temporalis scales covers part of the temporal lobe of the brain, it is part of the middle cranial fossa, and in it impressions of the cerebral convolutions and a deep groove for the middle meningeal artery are observed.
