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
You have been referred a middle–aged patient to rule out open angle glaucoma. Which of the following findings will help in the diagnosis – 
Select and explain. 
A. Cupping of the disc, B. Depth of anterior chamber, C. Visual acuity and refractive error, D. Angle of the anterior chamber
A: Cupping of the disc
Answer: A: Cupping of the disc 
Explanation: At least two of the following three are required to make a diagnosis of POAG :-



Raised IOP (>21 mmHg) on more than one occasion and a circadian variation in TOP > 8 mmHg.
Glaucomatous changes in optic disc (including cupping of disc)
Visual field changes.