The correct answer is option 'C' - Solvent.

Explanation:
A solution is a mixture formed when a solute is dissolved in a solvent. In a solution, the solute is the substance that is dissolved, and the solvent is the liquid in which the solute is dissolved.

Here is a detailed explanation of the terms:

1. Solution:
A solution is a homogeneous mixture formed when a solute is dissolved in a solvent. It is a physical combination of two or more substances that are evenly distributed at a molecular level.

2. Solute:
The solute is the substance that is being dissolved in a solution. It is usually present in a smaller amount compared to the solvent. The solute can be a solid, liquid, or gas.

3. Solvent:
The solvent is the liquid component of a solution that dissolves the solute. It is usually present in a larger amount compared to the solute. The solvent has the ability to dissolve other substances, and it determines the physical state of the solution.

4. Mixture:
A mixture is a combination of two or more substances that are not chemically bonded together. Mixtures can be homogeneous (uniform composition) or heterogeneous (non-uniform composition).

In the context of the given question, the liquid in which a substance is dissolved is called the solvent. The solvent plays a crucial role in the formation of a solution as it allows the solute to dissolve and creates a homogeneous mixture.

For example, when salt (solute) is dissolved in water (solvent), it forms a saltwater solution. In this case, water acts as the solvent, and salt is the solute.

In summary, the liquid in which a substance is dissolved is called the solvent. It is an essential component of a solution as it dissolves the solute and creates a homogeneous mixture.

Solution