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
Typical iris coloboma is located at 
Select and explain. 
A. Supero - temporal quadrant, B. Supero - nasal quadrant, C. Infero - temporal quadrant, D. Infero - nasal quadrant
D: Infero - nasal quadrant
Answer: D: Infero - nasal quadrant 
Explanation: Iris coloboma :

It is congenital malformation due to failure to closure of choroidal or fetal tissue.
Most common site is infero - nasal quadrant.