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
Selective α2  agonist is: 
Select and explain. 
A. Clonidine, B. Prazosin, C. Adrenaline, D. Propranolol
A: Clonidine
Answer: A: Clonidine 
Explanation: None