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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Which aery is formed by joining of 2 veebral aeries?
assistant
The correct answer is  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)