Wildlife Conservation in Natural Habitats
Wildlife conservation is crucial for maintaining biodiversity and ensuring the survival of various species. Different protected areas play unique roles in conservation efforts.
Types of Protected Areas

• Sanctuaries:
  Wildlife sanctuaries provide a safe haven for animals and plants. They allow for natural habitats to thrive without human interference. The primary aim is to protect specific species that may be endangered or threatened.
  
• National Parks:
  National parks are larger areas that preserve entire ecosystems. These parks not only protect wildlife but also promote ecological research and education. They offer recreational opportunities while ensuring that habitats and species are not disturbed.
  
• Biosphere Reserves:
  Biosphere reserves are designated areas that aim to balance biodiversity conservation with sustainable development. They consist of core areas, buffer zones, and transition areas, allowing for the protection of wildlife while also supporting human communities.
  

Conclusion
In conclusion, all these protected areas—sanctuaries, national parks, and biosphere reserves—play integral roles in wildlife conservation. They each contribute to preserving natural habitats and ensuring the survival of diverse species. Thus, the correct answer is option 'D': all of these areas are essential for wildlife conservation.

Wildlife conservation in natural habitats is done in:
Sanctuaries:
- Sanctuaries are designated areas where wildlife is protected and conserved.
- They provide a safe haven for various species of animals and plants.
- These areas are managed and monitored to ensure the well-being of the wildlife.
National Parks:
- National parks are protected areas of land, typically owned by a national government, where wildlife and their habitats are conserved.
- They are established to preserve the natural environment and biodiversity.
- National parks often have specific regulations and restrictions to protect the wildlife and their habitats.
Biosphere Reserves:
- Biosphere reserves are designated areas that aim to conserve biodiversity while promoting sustainable development.
- They are larger than sanctuaries and national parks and typically include a core area, buffer zone, and transition area.
- Biosphere reserves focus on the conservation of ecosystems, species, and genetic diversity.
All of these:
- Wildlife conservation in natural habitats is done in all of the mentioned options.
- Sanctuaries, national parks, and biosphere reserves all play a crucial role in protecting and conserving wildlife and their habitats.
In conclusion, wildlife conservation in natural habitats is carried out in sanctuaries, national parks, and biosphere reserves. These designated areas provide protection and support for various species, ensuring their survival and promoting biodiversity conservation.