Assertion An actual gas behaves as an ideal gas most closely at low pressure and high temperature.
Reason At low pressure and high temperature, real gases obey the gasl laws.

Options

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

Explanation

To analyze the assertion and reason provided in the question, we will break down the concepts step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "An actual gas behaves as an ideal gas most closely at low pressure and high temperature."
- This is based on the fact that under these conditions, the behavior of real gases approximates that of ideal gases.

2. **Understanding Ideal Gas Behavior**:
- An ideal gas is defined as a hypothetical gas that perfectly follows the gas laws (PV=nRT) without any deviations.
- Ideal gases have no intermolecular forces and occupy no volume.

3. **Conditions for Ideal Behavior**:
- At **low pressure**, the volume occupied by gas molecules becomes negligible compared to the volume of the container, reducing the effects of molecular size.
- At **high temperature**, the kinetic energy of the gas molecules increases, which means they move faster and overcome any attractive forces between them.

4. **Understanding the Reason**:
- The reason states that "At low pressure and high temperature, real gases obey the gas laws."
- This is true because, under these conditions, the interactions between gas molecules are minimal, allowing them to behave more like ideal gases.

5. **Linking Assertion and Reason**:
- The assertion and reason are connected. The reason explains why the assertion is true: when intermolecular forces are negligible (as they are at low pressure and high temperature), real gases behave similarly to ideal gases.

6. **Conclusion**:
- Both the assertion and the reason are correct, and the reason provides a valid explanation for the assertion.

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