Oviparous mammals are

Options

A. Kangaroo
B. Duck bill platypus
C. Whale
D. Rabbit

Answer

### Step-by-Step Solution:

1. **Understanding Oviparous and Viviparous**:
- Oviparous animals are those that lay eggs.
- Viviparous animals give birth to live young ones.

2. **Defining Mammals**:
- Mammals are characterized by their ability to produce milk to nourish their young.

3. **Identifying Oviparous Mammals**:
- Among mammals, there are very few that are oviparous. The most notable example is the duck-billed platypus.

4. **Analyzing the Options**:
- **Kangaroo**: This is a viviparous mammal as it gives birth to live young and carries them in a pouch.
- **Duck-billed Platypus**: This is an oviparous mammal as it lays eggs and also feeds milk to its young.
- **Whale**: This is a viviparous mammal that gives birth to live young.
- **Rabbit**: This is also a viviparous mammal that gives birth to live young.

5. **Conclusion**:
- The only oviparous mammal among the options provided is the duck-billed platypus.

### Final Answer:
- The oviparous mammal is the **Duck-billed Platypus**.

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