This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nose and paranasal sinuses, Subject name: ENT
[{'content': "Kisselbach's plexus is formed by septal branches of all expect \nSelect and explain. \nA. Posterior ethmoidal aery, B. Anterior ethmoidal aery, C. Sphenopalatine aery, D. Greater palatine aery", 'role': 'user'}, {'content': "Answer: A \nExplanation: Kiesselbach's Plexus: Aerial plexus of Little's area Formed by s Septal branches of Anterior ethmoidal Superior labial Sphenopalatine Greater palatine aery Ref: Dhingra 7e pg 197.", 'role': 'assistant'}]