The most important human activity leading to the extincting of wildlife is

Options

A. Pollution of air and water
B. Hunting for valuable wildlife products
C. Introduction of alien species
D. Alteration and destruction of the natural habitats

Answer

### Step-by-Step Solution:

1. **Identify the Question**: The question asks for the most important human activity leading to the extinction of wildlife among the given options.

2. **List the Options**: The options provided are:
- Option 1: Pollution of air and water
- Option 2: Hunting for valuable wildlife products
- Option 3: Introduction of alien species
- Option 4: Alteration and destruction of natural habitat

3. **Analyze Each Option**:
- **Option 1**: Pollution of air and water can harm wildlife but does not directly lead to extinction on a large scale.
- **Option 2**: Hunting for valuable wildlife products can reduce populations but is not the primary cause of extinction.
- **Option 3**: Introduction of alien species can disrupt ecosystems but is not the most significant factor leading to extinction.
- **Option 4**: Alteration and destruction of natural habitat is a major cause of wildlife extinction as it forces organisms out of their natural environments.

4. **Determine the Correct Answer**: Based on the analysis, option 4, "Alteration and destruction of natural habitat," is identified as the most important human activity leading to the extinction of wildlife.

5. **Conclusion**: The correct answer to the question is option 4.