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: Pharmacology
[{'content': 'Triptans used in migraine headaches are agonists at which receptor : \nSelect and explain. \nA. 5HT ID/IB, B. 5HTIA, C. 5HT3, D. 5HT2A', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]