Assertion: Neptune take 165 years to complete one revolution around Sun.
Reason: Neptune is farthest planet from Sun.

Options

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

Answer

To solve the question regarding the assertion and reason about Neptune, we will analyze both statements step by step.

### Step 1: Understand the Assertion
The assertion states that "Neptune takes 165 years to complete one revolution around the Sun."
- **Explanation**: This is a factual statement. Neptune, being the eighth planet from the Sun, has a long orbital period due to its distance from the Sun. It indeed takes approximately 165 Earth years to complete one full orbit around the Sun.

### Step 2: Understand the Reason
The reason states that "Neptune is the farthest planet from the Sun."
- **Explanation**: This statement is also true. Neptune is the furthest planet in our solar system from the Sun, located at an average distance of about 30 astronomical units (AU) from the Sun, where 1 AU is the distance from the Earth to the Sun.

### Step 3: Analyze the Relationship Between Assertion and Reason
Now, we need to determine if the reason correctly explains the assertion.
- **Explanation**: The reason given is that Neptune is the farthest planet from the Sun, which directly relates to the assertion. As the distance from the Sun increases, the gravitational pull decreases, resulting in a slower orbital speed. This slower speed means that it takes longer for Neptune to complete its orbit, which is why it takes 165 years.

### Conclusion
Both the assertion and reason are true, and the reason correctly explains the assertion. Therefore, the correct answer is that both statements are true, and the reason is the correct explanation of the assertion.

### Final Answer
- Assertion: True
- Reason: True
- Explanation: The reason is the correct explanation of the assertion.

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