This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Brain , Subject name: Anatomy
Which aery is formed by joining of 2 veebral aeries? 
Select and explain. 
A. Basal aery, B. Middle cerebralaery, C. Posterior cerebral aery, D. Basilar aery
D: Basilar aery
Answer: D: Basilar aery 
Explanation: Basilar aery is formed by the union of two veebral aeries at the lower border of pons. Middle cerebral aery is a branch of internal carotid aery. Posterior cerebral aery is a branch of basilar aery. (Ref: Vishram Singh textbook of clinical neuroanatomy, second edition pg-174,176)