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
0.1 to 0.2 mm nebular corneal opacity is treated by – 
Select and explain. 
A. Penetrating keratoplasty, B. Lamellar keratoplasty, C. Enucleation, D. Evisceration
B: Lamellar keratoplasty
Answer: B: Lamellar keratoplasty 
Explanation: Central nebular opacity is treated by phototherapeutic keratectomy with an excimer laser (treatment of choice) or lamellar keratoplasty.