The correct answer is (d). Maintenance of ecosystem.
Biodiversity is the variety of life on Earth. It includes the variety of plants, animals, and microorganisms, as well as the variety of ecosystems, which are communities of organisms interacting with their environment. Biodiversity is important for many reasons, including:
- Food: Humans rely on biodiversity for food. We eat plants, animals, and fungi, and we also use plants for medicines and other products.
- Medicines: Many of the medicines we use come from plants and animals. For example, aspirin comes from willow bark, and quinine comes from the bark of the cinchona tree.
- Industrial use: Biodiversity is also used in industry. For example, rubber comes from rubber trees, and cotton comes from cotton plants.
- Maintenance of ecosystem: Biodiversity is essential for the maintenance of ecosystems. Ecosystems provide us with many services, such as clean air and water, and they help to regulate the climate.
The other options are also important, but they are not as significant as the maintenance of ecosystem. Food, drugs, and industrial use are all important, but they can be replaced by other resources. For example, we can grow food in artificial environments, and we can develop new drugs from synthetic chemicals. However, the maintenance of ecosystem is essential for life on Earth.