This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Glaucoma, Subject name: Ophthalmology
Drug of choice for primary open angle glaucoma: 
Select and explain. 
A. Beta blockers, B. Prostaglandin analogues, C. Alpha agonists, D. Cholinergics
B: Prostaglandin analogues
Answer: B: Prostaglandin analogues 
Explanation: Prostaglandin analogues are now the drug of choice for open angle glaucoma and normal tension glaucoma.