Mammals having traits of both reptiles and mammals are

Options

A. Monotremes
B. Marsupials
C. Whales
D. Bats

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for mammals that exhibit traits of both reptiles and mammals. This indicates that we are looking for a specific group of mammals that serve as a link between these two classes.

2. **Identifying the Group**: The group of mammals that fits this description is known as "monotremes." Monotremes are unique because they lay eggs, which is a trait associated with reptiles.

3. **Characteristics of Monotremes**:
- **Egg-laying**: Unlike most mammals that give birth to live young, monotremes lay eggs.
- **Lack of Teats**: Monotremes do not have teats, which is a common feature in most mammals.
- **Reptile-like Features**: They possess several reptilian characteristics, such as a highly modified snout and beaks.

4. **Mammalian Traits**: Despite their reptilian traits, monotremes also exhibit mammalian characteristics, such as having hair on their bodies.

5. **Examples of Monotremes**: The two primary examples of monotremes are:
- Duck-billed platypus
- Echidna

6. **Conclusion**: Based on the characteristics and examples discussed, the correct answer to the question is "monotremes."

**Final Answer**: Mammals having traits of both reptiles and mammals are called monotremes.

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