This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pharmacology
[{'content': 'Which of the following drug is alpha 2 agonist? \nSelect and explain. \nA. Apraclonidine, B. Timolol, C. PG analogues, D. PG analogues', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Apraclonidine - Selective alpha 2 agonist. Useful in glaucoma. Alpha agonists (Brimonidine and apraclonidine) are contraindicated in hypeensive crisis. Dipivefrin is a prodrug which is conveed into epinephrine inside ttre eyeUall, so can safely be used in hypeension. REF : katzung pharmacology : 14th ed', 'role': 'assistant'}]