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: Anatomy
[{'content': "Vertical crest in the fundus of the internal auditory canal is k/a - \nSelect and explain. \nA. Bill's bar, B. Ponticulus, C. Cog, D. Falciform crest", 'role': 'user'}, {'content': "Answer: A \nExplanation: The internal acoustic canal is divided by transverse crest (or Falciform crest) into a superior and inferior part. The superior part is divided by vertical crest or Bill's bar into anterior and posterior parts.", 'role': 'assistant'}]