Given below are two statements: one is labelled as Assertion (A)...

The speed of light in a medium is given by $v = \dfrac{c}{\sqrt{\mu_r \epsilon_r}}$, where $c$ is the speed of light in vacuum, $\mu_r$ is the relative permeability, and $\epsilon_r$ is the relative permittivity of the medium.

For any transparent material medium, the relative permittivity (dielectric constant) $\epsilon_r > 1$ and relative permeability $\mu_r \approx 1$ (for non-magnetic materials) or slightly different, making their product $\mu_r \epsilon_r > 1$.

Since the denominator is greater than 1, the speed of light in the medium $v$ is always less than $c$. Thus, the Assertion is true.

The Reason states that the product is less than 1, which is physically incorrect for transparent media. Therefore, (A) is true but (R) is false.

Answer: (A) is true but (R) is false.