Assertion (A) : Excessive use of chlorinated synthetic pesticides causes soil and water pollution.
Reason (R) : Such pesticides are non-biodegradable.

Options

A. Both A and R are correct and R is the correct explanation of A
B. Both A and R are correct and R is not the correct explanation of A
C. Both A and R are not correct
D. A is not correct but R is correct

Explanation

### Step-by-Step Text Solution

1. **Understanding the Assertion**: The assertion states that excessive use of chlorinated synthetic pesticides causes soil and water pollution. This is true because these pesticides can leach into the soil and water bodies, leading to contamination.

2. **Impact on Soil and Water**: When chlorinated synthetic pesticides are applied, they can bind to soil particles and, through runoff or leaching, enter water bodies. This results in the pollution of both soil and water, making them unsafe for agricultural use and harming aquatic ecosystems.

3. **Understanding the Reason**: The reason provided is that such pesticides are non-biodegradable. This means that they do not break down naturally in the environment. Instead, they persist in the soil and water for extended periods, leading to long-term pollution.

4. **Connection Between Assertion and Reason**: The non-biodegradable nature of these pesticides is a significant factor in their ability to cause pollution. If they were biodegradable, they would decompose and potentially enrich the soil rather than pollute it. Therefore, the reason supports the assertion.

5. **Conclusion**: Both the assertion and the reason are correct, and the reason provided is indeed the correct explanation for the assertion. Thus, the answer to the question is that both the assertion and reason are true, and the reason correctly explains the assertion.