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
The most frequent cataract type seen in adult Retinitis pigmentosa patient is – 
Select and explain. 
A. PSC, B. Anterior polar, C. Cortical, D. Mixed
A: PSC
Answer: A: PSC 
Explanation: Retinitis pigmentosa is associated with posterior subcapsular cataract (PSC).

"Retinal pigment degenerations such as retinitis pigmentosa , Usher's syndrome and gyrate atrophy are associated with cataract, which are usually subcapsular opacities".

—Yanoff & Duker