Assertion: When two unlike charges are brought nearer, their electrostatic potentiasl energy decreases.
Reason: All conservative forces act in the direction of decreasing potential energy.

Options

A. If both Assertion and Reason are true but 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 the Reason is false.
D. If Assertion is false but the Reason is true.

Explanation

To analyze the given assertion and reason, we will break down the concepts of electrostatic potential energy and conservative forces step by step.

### Step 1: Understand the Assertion
The assertion states that when two unlike charges are brought closer together, their electrostatic potential energy decreases.

**Explanation**:
- The potential energy (U) between two point charges \( q_1 \) and \( q_2 \) is given by the formula:
\[ U = \frac{k \cdot q_1 \cdot q_2}{r} \]
where \( k \) is Coulomb's constant and \( r \) is the distance between the charges.
- For unlike charges (one positive and one negative), \( q_1 \cdot q_2 < 0 \). Therefore, as \( r \) decreases (the charges come closer), the absolute value of \( U \) becomes larger but remains negative, indicating that the potential energy decreases.

### Step 2: Understand the Reason
The reason states that all conservative forces act in the direction of decreasing potential energy.

**Explanation**:
- A conservative force is defined as a force where the work done is independent of the path taken and depends only on the initial and final positions.
- The work done by conservative forces results in a change in potential energy. Therefore, as an object moves in the direction of the force, the potential energy decreases.

### Step 3: Analyze the Relationship
Now, we need to determine if the reason correctly explains the assertion.

- The assertion is true: when two unlike charges are brought closer, their potential energy decreases.
- The reason is also true: conservative forces act in the direction of decreasing potential energy.
- However, the reason does not specifically explain why the potential energy decreases when unlike charges are brought closer. It is a general statement about conservative forces, not directly related to the behavior of electrostatic potential energy in this context.

### Conclusion
- The assertion is true.
- The reason is true, but it does not serve as a correct explanation for the assertion.

Thus, the correct answer is that both the assertion and reason are true, but the reason is not a correct explanation for the assertion.

### Final Answer
**Assertion**: True
**Reason**: True
**Explanation**: The reason does not specifically explain the assertion.

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