Assertion : When we bring a magnet close to a pin lying on a smooth table, the pin starts moving (sliding) towards the magnet.
Reason : Magnetic force is a contact force.

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 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 1: Understanding the Assertion
The assertion states that when a magnet is brought close to a pin lying on a smooth table, the pin starts moving towards the magnet.

- **Explanation**: This is true because a pin made of a magnetic material (like iron) will experience a magnetic force when a magnet is brought near it. The magnet creates a magnetic field that can attract the pin, causing it to slide towards the magnet.

### Step 2: Understanding the Reason
The reason provided states that magnetic force is a contact force.

- **Explanation**: This statement is false. Magnetic force is actually a non-contact force. It can act over a distance without the need for the magnet and the magnetic material to be in direct contact. For example, a magnet can attract a pin from a distance without touching it.

### Step 3: Conclusion
Based on the analysis:
- The assertion is **true** because the pin does move towards the magnet due to the attractive magnetic force.
- The reason is **false** because magnetic force is not a contact force; it can act at a distance.

### Final Answer
The correct option is that the assertion is true, but the reason is false.

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