The solution in which the light is not scattered by the particles is:

Options

A. Suspension
B. Colloidal solution
C. True solution
D. None of these

Answer

To solve the question, "The solution in which the light is not scattered by the particles is:", we will analyze the different types of mixtures and their properties regarding light scattering.

### Step-by-Step Solution:

1. **Understanding the Types of Mixtures**:
- There are three main types of mixtures: solutions, colloids, and suspensions. Each has distinct characteristics regarding particle size and light scattering.

2. **Definition of a Solution**:
- A solution is a homogeneous mixture where one substance (the solute) is completely dissolved in another (the solvent). The particle size in a true solution is typically less than 1 nanometer, which is much smaller than the wavelength of visible light.

3. **Light Scattering in Solutions**:
- In a true solution, the particles are so small that they do not scatter light. This means that when light passes through a true solution, it remains unscattered, and you cannot see a beam of light passing through it.

4. **Colloidal Solutions**:
- In a colloidal solution, the particle size ranges from 1 nanometer to 1000 nanometers. These particles are large enough to scatter light, which is known as the Tyndall effect. Therefore, light is scattered in colloidal solutions.

5. **Suspensions**:
- Suspensions consist of larger particles that can settle over time. These particles are also large enough to scatter light, so light will be scattered in suspensions as well.

6. **Conclusion**:
- Since only true solutions do not scatter light, the correct answer to the question is that the solution in which the light is not scattered by the particles is a **true solution**.

### Final Answer:
The solution in which the light is not scattered by the particles is a **true solution**.

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