Air is an example of:

Options

A. Human resource
B. Man-made resource
C. Natural resource
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what type of resource air is categorized as. The options provided are human resource, manmade resource, natural resource, and none of these.

2. **Defining the Options**:
- **Human Resource**: This refers to the human labor and skills that contribute to the production of goods and services.
- **Manmade Resource**: This refers to resources that are created or manufactured by humans, such as buildings, machinery, and synthetic materials.
- **Natural Resource**: This refers to resources that occur naturally in the environment without human intervention, such as water, minerals, and air.
- **None of These**: This option indicates that the answer does not fit into any of the previous categories.

3. **Analyzing Air**: Air is composed of a mixture of gases, primarily nitrogen and oxygen, and it exists in the environment without any human intervention. Therefore, it is not created or altered by humans.

4. **Conclusion**: Based on the definitions and analysis, air is classified as a **natural resource** because it is available in nature and produced by natural processes.

**Final Answer**: Air is an example of a **natural resource**.

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