Back of credit cards/ATM cards are designed with metal strip made of

Options

A. copper
B. gold
C. magnet
D. none of these

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the material used in the metal strip found on the back of credit cards and ATM cards.

2. **Identifying the Strip**: The metal strip on the back of these cards is commonly known as the magnetic stripe. It is the area where information is encoded.

3. **Material Composition**: The magnetic stripe is not made of traditional metals like copper or gold. Instead, it is made of a magnetic material that allows it to store data.

4. **Conclusion**: Based on the information, we can conclude that the metal strip on the back of credit cards and ATM cards is made of a magnetic material.

5. **Final Answer**: Therefore, the correct answer to the question is that the back of credit cards and ATM cards are designed with a metal strip made of **magnet**.

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