This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autonomic nervous system, Subject name: Pharmacology
[{'content': 'Tamsulosin is a competitive antagonist for which of the following receptors? \nSelect and explain. \nA. Alpha 1A, B. alpha 2, C. beta 1, D. beta 2', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Tamsulosin is an alpha 1 blocker with a higher activity for alpha 1A and alpha 1D receptors. Ref: Padmaja 4th edition page no 104', 'role': 'assistant'}]