Which of the following mammal is oviparous?

Options

A. Macropus
B. Pteropus
C. Ornithorhynchus
D. Delphinus

Answer

To determine which mammal is oviparous, we need to understand the definitions and classifications of mammals:

1. **Understanding Oviparous**: Oviparous refers to organisms that lay eggs. Most mammals are viviparous, meaning they give birth to live young.

2. **Identifying Mammal Categories**: Mammals can be classified into three main groups:
- **Monotremes**: These are egg-laying mammals.
- **Marsupials**: These give birth to underdeveloped young that continue to develop in a pouch.
- **Eutherians**: These are placental mammals that give birth to more fully developed young.

3. **Identifying Oviparous Mammals**: Among mammals, the only group that is oviparous is the monotremes. The most well-known example of a monotreme is the duck-billed platypus.

4. **Analyzing the Options**: The question provides several options:
- **Macropus**: This is the scientific name for kangaroos, which are marsupials and viviparous.
- **Pteropus**: This refers to flying foxes, which are also viviparous.
- **Ornithorhynchus**: This is the scientific name for the duck-billed platypus, which is oviparous.
- **Delphinus**: This refers to dolphins, which are eutherians and viviparous.

5. **Conclusion**: Based on the classifications and the analysis of the options, the only oviparous mammal listed is **Ornithorhynchus** (duck-billed platypus).

**Final Answer**: The oviparous mammal is **Ornithorhynchus** (duck-billed platypus).

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