This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: A.N.S., Subject name: Pharmacology
[{'content': 'Tizanidine has action on: \nSelect and explain. \nA. Alpha adrenergic, B. GABA A action, C. Gaba B action, D. Beta adrenergic', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. a. Alpha adrenergicRef: Goodman Gilman 13th E/P203Alpha-2 AgonistsClonidineDexmedetomidineLofexidineMethyldopaTizanidineGuanfacineGuanabenzMoxonidineApraclonidineBrimonidine', 'role': 'assistant'}]