A: The magnetic field lines also represent the lines of force on a moving charged particle at every point.
R: Force on a moving charge acts parallel to the magnetic field.

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 question, we need to analyze both the assertion (A) and the reason (R) provided.

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states: "The magnetic field lines also represent the lines of force on a moving charged particle at every point."
- Magnetic field lines indicate the direction of the magnetic field at various points in space. However, they do not represent the lines of force acting on a moving charged particle. The force experienced by a charged particle moving in a magnetic field is determined by the Lorentz force law.

2. **Understanding the Reason (R)**:
- The reason states: "Force on a moving charge acts parallel to the magnetic field."
- According to the Lorentz force law, the force \( \mathbf{F} \) on a moving charge \( q \) in a magnetic field \( \mathbf{B} \) is given by the equation:
\[ \mathbf{F} = q(\mathbf{v} \times \mathbf{B}) \]
- This equation indicates that the force is perpendicular to both the velocity \( \mathbf{v} \) of the charge and the magnetic field \( \mathbf{B} \). Therefore, the statement that the force acts parallel to the magnetic field is incorrect.

3. **Conclusion**:
- Since both the assertion and the reason are false, we conclude that both statements do not hold true.

### Final Answer:
Both the assertion (A) and the reason (R) are false.