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 angle closure glaucoma, obstruction to outflow of aqueous humour mainly due to the involvement of: September 2007 
Select and explain. 
A. Canal of schlemm, B. Trabecular meshwork, C. Iris, D. Scleral venous plexus
C: Iris
Answer: C: Iris 
Explanation: Ans. C: Iris