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
Fincham's test differentiates cataract from - 
Select and explain. 
A. Conjunctivitis, B. Iridocyclitis, C. Open angle Glaucoma, D. Ac. Congestive Glaucoma
D: Ac. Congestive Glaucoma
Answer: D: Ac. Congestive Glaucoma 
Explanation: The halos of glaucoma and immature cataract may be differentiated by Fincham's test in which a stenopaeic slit is passed across the pupil . During this test , glaucomatous halo remains intact, while a halo due to cataract is broken up into segments . Ref: Comprehensive Ophthalmology AK Khurana 6th edition chapter-10 page no: 244