This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Other topics and Adverse effects, Subject name: Anatomy
Agonistic action at which of the following adrenergic receptor result in the reduction of excess secretion 
Select and explain. 
A. Beta 1 receptor, B. Beta 2 receptor, C. M2 receptor, D. Alpha 2 receptor
D: Alpha 2 receptor
Answer: D: Alpha 2 receptor 
Explanation: Ref-KDT 6/e p146 Stimulation of Alpha 2 receptors located on ciliary epithelium reduces secretion of aqueous humor.