Assertion : Petroleum or crude oil pumped out of oil well is not pure.
Reason : Petroleum is refined to get various fractions which can be used for a specific purpose.

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.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that petroleum or crude oil pumped out of oil wells is not pure. This is true because crude oil is a natural resource that is found beneath the Earth's surface and is often mixed with various impurities such as water, soil, and rock particles.

2. **Understanding the Reason**: The reason provided states that petroleum is refined to obtain various fractions that can be used for specific purposes. This is also true. The process of refining petroleum involves separating it into different components or fractions, each of which has its own specific uses (like gasoline, diesel, kerosene, etc.).

3. **Connecting Assertion and Reason**: Both the assertion and reason are correct and are related. The fact that crude oil is not pure (assertion) leads to the necessity of refining it (reason) to obtain useful products.

4. **Conclusion**: Therefore, both the assertion and the reason are true, and the reason correctly explains the assertion.