Which of the following decides the type of reflection?

Options

A. Difference in the type of surface
B. Difference in the type of incident light
C. Difference in size of the normal
D. Difference in the type of reflected light

Answer

To determine which factor decides the type of reflection, we need to analyze the options provided:

1. **Difference in the type of surface**:
- The type of surface plays a crucial role in determining the type of reflection.
- If the surface is smooth and polished, the reflection is regular (or specular) reflection, where light rays reflect at the same angle they hit the surface.
- Conversely, if the surface is rough, the reflection is diffused reflection, where light rays scatter in multiple directions.

2. **Difference in the type of incident light**:
- This option suggests that the angle or type of incident light affects the type of reflection. However, this is incorrect. The type of reflection primarily depends on the surface texture rather than the incident light.

3. **Difference in the size of the normal**:
- The normal is a line perpendicular to the surface at the point of incidence. The size of the normal does not affect the type of reflection, as it is always perpendicular to the surface.

4. **Difference in the type of the reflected light**:
- This option implies that the type of light being reflected can determine the type of reflection. However, this is also incorrect. The type of reflection is determined by the surface characteristics, not the nature of the reflected light.

Based on the analysis of the options, we conclude that the correct answer is:

**The type of surface decides the type of reflection.**

### Step-by-Step Summary:
1. **Identify the role of the surface**: Smooth surfaces lead to regular reflection, while rough surfaces lead to diffused reflection.
2. **Evaluate the impact of incident light**: The type of incident light does not determine the type of reflection.
3. **Consider the normal**: The size of the normal does not influence the reflection type.
4. **Assess the reflected light**: The type of reflected light does not dictate the reflection type.