Red Data Book' or `IUCN` Red List provides data on

Options

A. Biota of Red sea
B. Effect of red light or photosynthesis
C. Red pigmented plants
D. Threatened species.

Answer

**Step-by-Step Solution:**

1. **Understanding the Red Data Book/IUCN Red List**: The Red Data Book, also known as the IUCN Red List, is a comprehensive inventory that provides information on the global conservation status of biological species.

2. **Purpose of the IUCN Red List**: The primary purpose of the IUCN Red List is to assess the risk of extinction faced by various species. It categorizes species based on their conservation status.

3. **Categories of Threatened Species**: The IUCN Red List classifies species into three main categories based on their level of threat:
- **Vulnerable Species**: Species that are at risk of becoming endangered in the near future.
- **Endangered Species**: Species that are facing a very high risk of extinction in the wild.
- **Critically Endangered Species**: Species that are facing an extremely high risk of extinction in the wild.

4. **Statistics from the Red List**: As of the year 2000, the Red List reported a total of 11,096 species that are considered threatened. This includes a variety of organisms such as animals, plants, and fungi.

5. **Conclusion**: Therefore, the IUCN Red List provides data specifically on threatened species, which are those that are at risk of extinction.

**Final Answer**: The 'Red Data Book' or 'IUCN Red List' provides data on threatened species.

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