Assertion: Census is held in India after every ten years.
Reason: Scientific study of population is called demography

Options

A. If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
B. If both Assertion and Reason are true and the Reason is not the correct explanation of the Assertion.
C. If Assertion is true but the Reason is false
D. If both Assertion and Reason are false.

Explanation

To solve the question, we need to analyze the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Census is held in India after every ten years."
- This is true. The Census of India is conducted every ten years, with the most recent one being in 2011. The first complete census was conducted in 1881, and this practice has continued since then.

2. **Understanding the Reason**:
- The reason states that "Scientific study of population is called demography."
- This is also true. Demography is indeed the scientific study of populations, including the structure, distribution, and trends in population changes.

3. **Analyzing the Relationship**:
- Now we need to determine if the reason is a correct explanation of the assertion.
- While both statements are true, the reason does not directly explain why the census is conducted every ten years. The assertion is about the frequency of the census, while the reason describes what demography is.

4. **Conclusion**:
- Since both the assertion and reason are true, but the reason does not explain the assertion, the correct option is:
- "If both assertion and reason are true, the reason is not the correct explanation of the assertion."

### Final Answer:
The correct option is: **If both assertion and reason are true, the reason is not the correct explanation of the assertion.**

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