Which of the following can be turned into a magnet?

Options

A. Copper coil
B. Glass bowl
C. Plastic toy
D. Nickel disc

Explanation

To determine which of the given options can be turned into a magnet, we need to identify which of the materials listed is a magnetic material. Here’s a step-by-step solution:

### Step 1: Understand the concept of magnetism
Magnetism is a property of certain materials that allows them to be attracted to magnets or to become magnets themselves. Materials that can be turned into magnets are known as magnetic materials.

### Step 2: Analyze each option
1. **Copper coil**: Copper is a non-magnetic material. It does not have the properties to be magnetized.
2. **Glass bowl**: Glass is also a non-magnetic material. It cannot be magnetized.
3. **Plastic toy**: Plastic is a non-magnetic material. It cannot be turned into a magnet.
4. **Nickel disc**: Nickel is a magnetic material. It can be magnetized and can become a magnet.

### Step 3: Identify the correct answer
From the analysis, we see that only the nickel disc is a magnetic material that can be turned into a magnet. Therefore, the correct answer is option 4: **Nickel disc**.

### Final Answer:
The correct option that can be turned into a magnet is **Nickel disc** (Option 4).

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