This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
Posterior communicating aery a branch of 
Select and explain. 
A. Internal carotid, B. External carotid, C. Middle cerebral, D. Posterior superior cerebellar
A: Internal carotid
Answer: A: Internal carotid 
Explanation: Posterior communicating aery is a branch of internal carotid which connects posterior cerebral aery Ref: Gray's 40e/p-250-251