A: magnetic field lines are continuous and form closed loops.
R: Magnetic monopoles do not exist.

Options

A. If both Assertion & Reason are the true and the reason is the correct explanation of the assertion, then mark (1)
B. If both Assertion & Reason are true but the reson is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason are false statements, then mark (4)

Answer

To solve the assertion and reason question, we will analyze both the assertion (A) and the reason (R) step by step.

### Step 1: Analyze the Assertion (A)
The assertion states that "magnetic field lines are continuous and form closed loops."

- **Explanation**: Magnetic field lines represent the direction and strength of the magnetic field. They emerge from the north pole of a magnet and enter into the south pole, forming closed loops. Inside the magnet, the field lines run from the south pole back to the north pole. This continuity and loop formation is a fundamental characteristic of magnetic fields.

### Step 2: Analyze the Reason (R)
The reason states that "magnetic monopoles do not exist."

- **Explanation**: A magnetic monopole would be a particle that has only one magnetic pole (either a north or a south pole). However, experiments and theoretical physics suggest that magnetic monopoles do not exist in nature. Whenever a magnet is divided, it results in two smaller magnets, each with both a north and a south pole. This indicates that magnetic monopoles cannot be isolated.

### Step 3: Determine the Relationship Between A and R
Now, we need to evaluate if the reason correctly explains the assertion.

- The assertion is true because magnetic field lines are indeed continuous and form closed loops.
- The reason is also true because magnetic monopoles have not been observed, supporting the concept of closed magnetic field lines.

### Conclusion
Since both the assertion and reason are true, and the reason provides a correct explanation for the assertion, we conclude that:

**Both assertion and reason are true, and the reason is a correct explanation of the assertion.**

### Final Answer
Option A: Both assertion and reason are true, and reason is a correct explanation of assertion.

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