A red list of endangered species is maintained by :

Options

A. CSIR
B. IUCN
C. NEERI
D. WLS.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the organization that maintains a red list of endangered species.

2. **Identifying the Options**: The options provided are:
- A) CSIR
- B) IUCN
- C) NIDI
- D) WNS

3. **Researching Each Option**:
- **CSIR (Council of Scientific and Industrial Research)**: This is an Indian research and development organization, not specifically focused on biodiversity conservation.
- **IUCN (International Union for Conservation of Nature and Natural Resources)**: This organization is known for its work in biodiversity conservation and is responsible for the Red List of Threatened Species.
- **NIDI**: This acronym does not correspond to a well-known organization related to biodiversity conservation.
- **WNS (White-nose Syndrome)**: This refers to a disease affecting bats, not an organization.

4. **Conclusion**: Based on the research, the IUCN is the organization that maintains the red list of endangered species. The red list is a comprehensive global approach for evaluating the conservation status of plant and animal species.

5. **Final Answer**: Therefore, the correct answer to the question is **B) IUCN**.

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