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
Which one of the following is not a target disease under 'Vision 2020: The Right to Sight' 
Select and explain. 
A. Refractive error, B. Trachoma, C. Corneal blindness, D. Diabetic retinopathy
D: Diabetic retinopathy
Answer: D: Diabetic retinopathy 
Explanation: Ans. is `d' i.e., Diebitic retinopathy