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: ENT
[{'content': "Kisselbach's plexus is formed by septal branches of all except - \nSelect and explain. \nA. Posterior ethmoidal artery, B. Anterior ethamoidal artery, C. Sphenopalatine artery, D. Greater palatine artery", 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]