Which of the following is not a magnetic material?

Options

A. Iron
B. Nickel
C. Cobalt
D. Copper

Explanation

To determine which of the following is not a magnetic material, we need to understand the difference between magnetic and non-magnetic materials.

### Step-by-Step Solution:

1. **Define Magnetic Materials**:
- Magnetic materials are those that are attracted to magnets and can be magnetized themselves. Common examples include iron, cobalt, and nickel.

2. **Define Non-Magnetic Materials**:
- Non-magnetic materials are not attracted to magnets and cannot be magnetized. Examples of non-magnetic materials include copper, paper, plastic, and wood.

3. **Identify the Options**:
- Look at the options provided in the question. We need to identify which one does not belong to the category of magnetic materials.

4. **Analyze Each Option**:
- If the options include iron, nickel, cobalt, and copper:
- Iron: Magnetic
- Nickel: Magnetic
- Cobalt: Magnetic
- Copper: Non-Magnetic

5. **Select the Correct Answer**:
- Since copper is the only material in the options that is not magnetic, it is the correct answer to the question.

### Final Answer:
The material that is not a magnetic material is **copper**.

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