This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anti Adrenergic System, Subject name: Pharmacology
Drug used in Benign Prostatic Hypertrophy is? 
Select and explain. 
A. a1agonist, B. a1. antagonist, C. a2, agonist, D. a2 antagonist
B: a1. antagonist
Answer: B: a1. antagonist 
Explanation: ANSWER: (B) a, antagonistsREF: KDT 7th ed p-135, Goodman and Gillman's 11th ed page 172,173,183