Incorrect statement in the following.

Options

A. CO poisoning reduces `O_(2)` carrying capacity by
B. Los-angel smog and London smog are examples for secondary pollutants
C. Favourable changes in climatic conditions is EL Nino effect
D. Habitat destruction leads to loss of biodiversity

Answer

To solve the question about identifying the incorrect statement among the given options, we can follow these steps:

### Step-by-Step Solution:

1. **Examine the First Statement**:
- The first statement mentions that "carbon monoxide poisoning reduces oxygen carrying capacity."
- This statement is generally true as carbon monoxide binds with hemoglobin more effectively than oxygen, thus reducing the oxygen carrying capacity of the blood.

2. **Examine the Second Statement**:
- The second statement claims that "Los Angeles smoke and London smoke are examples of secondary pollutants."
- This statement is also true. Secondary pollutants are formed in the atmosphere through chemical reactions, and both types of smoke are indeed classified as secondary pollutants.

3. **Examine the Third Statement**:
- The third statement states that "favorable changes in climatic condition is El Niño effect."
- This statement is incorrect. The El Niño effect is often associated with unfavorable climatic changes, such as increased rainfall and temperature anomalies, rather than favorable conditions.

4. **Examine the Fourth Statement**:
- The fourth statement asserts that "habitat destruction leads to the loss of biodiversity."
- This statement is true. Habitat destruction is one of the leading causes of biodiversity loss.

5. **Conclusion**:
- Based on the analysis, the incorrect statement is the third one regarding the El Niño effect. Therefore, the answer to the question is the third statement.

### Final Answer:
The incorrect statement is: "Favorable changes in climatic condition is El Niño effect."

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