An example of magnetic matter is:

Options

A. Aluminium
B. Gold
C. Mica
D. Steel

Explanation

To determine an example of magnetic matter from the given options (aluminium, gold, mica, or steel), we can follow these steps:

### Step 1: Understand the Types of Magnetic Matter
Magnetic matter can be classified into three categories: ferromagnetic, paramagnetic, and diamagnetic. Ferromagnetic materials are strongly attracted to magnets, while paramagnetic materials are weakly attracted, and diamagnetic materials are repelled by magnets.

### Step 2: Analyze Each Option
- **Aluminium**: This is a non-magnetic material. It does not exhibit any magnetic properties and is classified as paramagnetic, meaning it is weakly attracted to a magnet.

- **Gold**: Gold is also a non-magnetic material. It is classified as diamagnetic, which means it is repelled by a magnet.

- **Mica**: Mica is a non-magnetic material as well. It does not show any significant magnetic properties.

- **Steel**: Steel is a magnetic material. It is primarily composed of iron, which is ferromagnetic. This means steel is attracted to magnets and can exhibit strong magnetic properties.

### Step 3: Conclusion
Among the given options, the only example of magnetic matter is **steel**.

### Final Answer
**Steel** is an example of magnetic matter.

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