An egg - laying mammals is

Options

A. Kangaroo
B. Platypus
C. Koala
D. Whale

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for an example of an egg-laying mammal.

2. **Defining Key Terms**:
- **Oviparous**: Animals that lay eggs.
- **Viviparous**: Animals that give birth to live young.

3. **Identifying Mammal Types**:
- Most mammals are viviparous, meaning they give birth to live young.
- However, there are exceptions known as **monotremes**, which are egg-laying mammals.

4. **Listing the Options**: The options provided are kangaroo, platypus, koala, and whale.

5. **Analyzing Each Option**:
- **Kangaroo**: This is a marsupial and is viviparous as it gives birth to live young.
- **Platypus**: This is a monotreme and is known for laying eggs.
- **Koala**: This is also a marsupial and is viviparous.
- **Whale**: Whales are mammals that give birth to live young and are therefore viviparous.

6. **Conclusion**: The only egg-laying mammal from the options provided is the **platypus**.

**Final Answer**: The egg-laying mammal is the **platypus**.

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