Which of the following is the most important cause of animals and plants being to extinction ?

Options

A. Alien species invasion
B. Habitat loss and fragmentation
C. Co-extinctions
D. Over-explotations

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the most important cause of extinction in animals and plants.

2. **Understand the Context**: Extinction refers to the end of an organism's existence. The question is focused on the causes of extinction, particularly in the context of human impact on the environment.

3. **List Major Causes of Extinction**: According to the video transcript, several causes of extinction are mentioned:
- Overexploitation
- Alien species invasion
- Co-extinction
- Habitat loss and fragmentation

4. **Analyze Each Cause**:
- **Overexploitation**: This involves humans excessively using resources from nature, leading to the decline of certain species. An example is the stellar sea cow, which went extinct due to human greed.
- **Alien Species Invasion**: When non-native species are introduced to an ecosystem, they can outcompete native species for resources, leading to their extinction.
- **Co-extinction**: This occurs when one species' extinction leads to the extinction of another species that relies on it, such as pollinators and the plants they pollinate.
- **Habitat Loss and Fragmentation**: This is the most significant cause of extinction. Human activities, such as deforestation, have led to significant loss of habitats, particularly in biodiverse areas like tropical rainforests.

5. **Determine the Most Important Cause**: Based on the analysis, habitat loss and fragmentation is identified as the most critical cause of extinction. This is due to the extensive impact it has on various species and ecosystems.

6. **Conclusion**: The most important cause of animals and plants becoming extinct is habitat loss and fragmentation, primarily driven by human activities.

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