Fluids are:

Options

A. Gas
B. Liquid
C. Gas as well as liquid
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Understanding the Definition of Fluids:**
- Fluids are substances that can flow. They do not have a fixed shape and can take the shape of their container.

2. **Identifying Types of Fluids:**
- There are two main types of fluids: liquids and gases.
- Liquids have a definite volume but no definite shape, meaning they will conform to the shape of their container.
- Gases also have no definite shape and will expand to fill the entire volume of their container.

3. **Examples of Fluids:**
- Common examples of liquids include water and milk. When placed in a container, they take the shape of that container.
- An example of a gas is air, which fills the entire space of the container it is in.

4. **Conclusion:**
- Since both liquids and gases can flow and do not have a definite shape, we conclude that fluids include both gases and liquids.

**Final Answer:**
Fluids are substances that can flow and include both gases and liquids.

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