Assertion : A biosphere reserve is a specified area.
Reason : No restriction on human activities has been imposed in biosphere reserve

Options

A. If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B. If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C. If the assertion is true but the reason is false
D. If both the assertion and reason are false

Explanation

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "A biosphere reserve is a specified area."
- This is true. A biosphere reserve is indeed a designated area that is recognized for its unique ecosystems and biodiversity.

2. **Understanding the Reason**:
- The reason provided is that "No restriction on human activities has been imposed in biosphere reserve."
- This statement is incorrect. While biosphere reserves allow for some human activities, there are restrictions in place to protect the biodiversity and ecosystems within these areas.

3. **Analyzing the Relationship**:
- The assertion is true, but the reason is false.
- In biosphere reserves, certain human activities may be allowed, particularly those that are sustainable and do not harm the environment, but there are regulations and restrictions to ensure conservation efforts.

4. **Conclusion**:
- Since the assertion is true and the reason is false, the correct answer is that the assertion is true but the reason is false.

### Final Answer:
The assertion is true, but the reason is false.

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