Assertion: By roughening the surface of a glass sheet its transparency can be reduced.
Reason: Glass sheet with rough surface absorbs more light.

Options

A. a. If both assertion and reason are true and reason is the correct explanation of assertion
B. b. If both assertion and reason are true but reason is not the correct explanation of assertion
C. c. If assertion is true but reason is false
D. d. If both assertion and reason are false

Explanation

To analyze the assertion and reason given in the question, we will break down the concepts step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that roughening the surface of a glass sheet can reduce its transparency.
- Transparency refers to the ability of light to pass through a material without being scattered or absorbed.

2. **Understanding the Reason**:
- The reason provided is that a glass sheet with a rough surface absorbs more light.
- Absorption of light occurs when light energy is taken in by the material rather than being transmitted through it.

3. **Analyzing the Effect of Surface Roughness**:
- When light strikes a smooth glass surface, it can pass through with minimal scattering and reflection, leading to higher transparency.
- Conversely, when the surface is rough, the light is scattered in various directions due to the irregularities on the surface. This scattering can lead to a reduction in the amount of light that successfully transmits through the glass.

4. **Scattering vs. Absorption**:
- In the case of rough glass, while some light may be absorbed, the primary effect of roughness is increased scattering.
- Increased scattering means that less light is transmitted through the glass, which contributes to the reduction in transparency.

5. **Conclusion on Assertion and Reason**:
- The assertion is true: roughening the glass surface does reduce its transparency.
- The reason is false: while rough surfaces scatter more light, they do not necessarily absorb more light; they primarily scatter light, which is the key factor in reducing transparency.

6. **Final Assessment**:
- Therefore, the correct conclusion is that the assertion is true, but the reason is false.

### Final Answer:
- The assertion is true, and the reason is false.