Assertion : Secondary air pollutants are formed by interacting among primary pollutants and are more toxic
Reason: DDT is secondary air pollutants

Options

A. If both are true with reason being correct explanation
B. Both true but reason is not correct explanation
C. assertion is true but reason is wrong
D. Both are wrong

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Secondary air pollutants are formed by interacting among primary pollutants and are more toxic."
- This is true. Secondary air pollutants, such as ozone (O3) and peroxyacetyl nitrate (PAN), are indeed formed through chemical reactions involving primary pollutants in the atmosphere. They can be more harmful than the primary pollutants themselves.

2. **Understanding the Reason**:
- The reason states that "DDT is a secondary air pollutant."
- This is false. DDT (Dichlorodiphenyltrichloroethane) is not an air pollutant at all; it is primarily a pesticide that contaminates soil and water. It does not fit the definition of a secondary air pollutant, which is formed in the atmosphere through reactions of primary pollutants.

3. **Evaluating the Options**:
- Since the assertion is true and the reason is false, the correct choice is: "Assertion is true but reason is wrong."

### Final Answer:
The correct option is: **Assertion is true but reason is wrong.**

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