The ecosystem services include

Options

A. maintenance of biodiversity
B. pollination of crop
C. pollination of crop
D. all of these.

Answer

**Step-by-Step Solution:**

1. **Understanding Ecosystem Services**: Ecosystem services are the benefits that humans derive from ecosystems. These services are crucial for maintaining the health of the environment and supporting human life.

2. **Identifying Components of Ecosystems**: Ecosystems consist of biotic (living) and abiotic (non-living) components. Biotic components include organisms such as plants, animals, and humans, while abiotic components include elements like water, soil, and air.

3. **Examples of Ecosystem Services**:
- **Maintenance of Biodiversity**: This service ensures a variety of species exist within an ecosystem, which contributes to resilience and stability. Biodiversity is essential for ecosystem functionality and provides resources for food, medicine, and other needs.
- **Pollination of Crops**: Pollination is a critical ecosystem service performed by various organisms, including insects (like bees) and some non-living factors (like wind). It is vital for the reproduction of many plants, including those that produce food crops.

4. **Conclusion**: Given that both the maintenance of biodiversity and the pollination of crops are recognized as ecosystem services, the correct answer to the question is "all of these," as it encompasses both mentioned services.

**Final Answer**: The ecosystem services include maintenance of biodiversity, pollination of crops, and therefore, the correct option is "all of these."

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