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
Neovascularization of iris is frequently seen in all/except – 
Select and explain. 
A. CRVO, B. Diabetic retinopathy, C. Fuch's heterochromic cyclitis, D. Congenital cataract
D: Congenital cataract
Answer: D: Congenital cataract 
Explanation: Causes of rubeosis iridis (neovascularization of iris)
Common :

Diabetic retinopathy (most common cause), central retinal vein occlusion, Eale's disease, siclde-cell retinopathy.

Rare causes :

Long standing retinal detachment, central retinal artery occlusion, intraocular inflammation (uveitis), intraocular tumors (choroidal melanoma, retinoblastoma), radiation retinopathy, ocular ischemic syndrome (carotid artery disease, carotid-cavernous fistula).