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: Social & Preventive Medicine
The screening strategy for prevention of blindness from diabetic retinopathy according to the NPCB involves - 
Select and explain. 
A. Opportunistic screening, B. High risk screening, C. Mass screening, D. Screening by Primary Care Physician
B: High risk screening
Answer: B: High risk screening 
Explanation: High risk screening is applied to the group which has increased risk of developing certain disease/cancer.
Diabetic retinopathy patients are at increased risk of developing blindness. Therefore, screening strategy for prevention of blindness from diabetic retinopathy is high risk screening.