## **Core Concept**
The WHO 'Vision 2020' programme aims to eliminate avoidable blindness by the year 2020. It focuses on several major causes of blindness and adopts specific strategies for their control. The `SAFE` strategy is one such approach.

## **Why the Correct Answer is Right**
The `SAFE` strategy stands for **S**urgery for trichiasis, **A**ntibiotics for infection, **F**acial cleanliness, and **E**nvironmental improvement. This strategy is specifically designed for the control and prevention of **trachoma**, which is a major cause of preventable blindness worldwide, especially in areas with poor sanitation and hygiene.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is incorrect because while cataract is a major cause of blindness globally, the `SAFE` strategy is not adopted for its control. Cataract surgery is a key intervention but does not involve the `SAFE` strategy.
- **Option B:** This option might seem plausible because vitamin A deficiency is a significant public health problem leading to night blindness. However, its control involves vitamin A supplementation, not the `SAFE` strategy.
- **Option C:** This option is incorrect because while onchocerciasis (river blindness) is another cause of blindness, its control involves vector control and ivermectin distribution, not the `SAFE` strategy.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that trachoma, caused by *Chlamydia trachomatis*, is targeted by the `SAFE` strategy under the WHO's Vision 2020. This strategy is crucial in endemic areas for preventing further transmission and complications leading to blindness.

## **Correct Answer:** . Trachoma