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: Ophthalmology
In primary open-angle glaucoma pilocarpine eye drops lowers the intraocular pressure by its direct action on the: 
Select and explain. 
A. Trabecular meshwork, B. Ciliary epithelium, C. Longitudinal fibres of the ciliary muscle, D. All of the above
C: Longitudinal fibres of the ciliary muscle
Answer: C: Longitudinal fibres of the ciliary muscle 
Explanation: Ans. Longitudinal fibres of the ciliary muscle