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
Persistant pupillary membrane originates from 
Select and explain. 
A. Collarete, B. Around pupil, C. Angle of anterior chamber, D. Root of iris
A: Collarete
Answer: A: Collarete 
Explanation: Persistant pupillary membrane

Developmental abnormality of iris.
Starts at iris collarette (thickest part of iris).