__________are the most restricted out of all protected areas.

Options

A. National parks
B. Wildlife sanctuary
C. Biosphere reserve
D. Zoo

Answer

**Step-by-Step Solution:**

1. **Understanding Protected Areas**: Begin by recognizing that there are different types of protected areas, each with varying levels of restrictions on human activities.

2. **Identifying Types of Protected Areas**: The main types of protected areas include:
- National Parks
- Wildlife Sanctuaries
- Biosphere Reserves
- Zoos

3. **Analyzing National Parks**: National Parks are designed for wildlife conservation, allowing limited human activities such as tourism. However, they are not the most restricted.

4. **Examining Wildlife Sanctuaries**: Wildlife Sanctuaries focus on protecting wild animals with very few human activities allowed. They are more restricted than National Parks.

5. **Considering Biosphere Reserves**: Biosphere Reserves aim to conserve both plants and animals, often allowing some human activities like agriculture. They are less restricted compared to Wildlife Sanctuaries.

6. **Looking at Zoos**: Zoos are facilities that keep animals in captivity for public viewing. They do not qualify as protected areas in the same sense, as they involve ex-situ conservation (animals are kept outside their natural habitat).

7. **Conclusion**: After evaluating all the types of protected areas, it is clear that Wildlife Sanctuaries are the most restricted out of all protected areas.

**Final Answer**: Wildlife Sanctuaries are the most restricted out of all protected areas.

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