A mammal which lays eggs instead of giving birth to offspring is

Options

A. Rabbit
B. Macropus
C. Duck-billed platypus
D. Whale

Answer

To answer the question "A mammal which lays eggs instead of giving birth to offspring is," we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Classification of Mammals**:
- Mammals are classified into three main groups:
- **Prototheria** (Monotremes) - egg-laying mammals.
- **Metatheria** (Marsupials) - mammals that give birth to underdeveloped young.
- **Eutheria** (Placental mammals) - mammals that give birth to fully developed young.

**Hint**: Remember the three groups of mammals and their reproductive methods.

2. **Identify the Characteristics of Each Group**:
- **Prototheria**: These are primitive mammals that lay eggs. The most well-known example is the duck-billed platypus.
- **Metatheria**: These include marsupials like kangaroos, which give birth to live young that continue developing in a pouch.
- **Eutheria**: This group includes most mammals, such as whales and rabbits, which give birth to live young.

**Hint**: Focus on the reproductive methods of each group to distinguish them.

3. **Evaluate the Given Options**:
- **Rabbit**: This is a marsupial (incorrect).
- **Macropus**: This refers to kangaroos, which are also marsupials (incorrect).
- **Duck-billed Platypus**: This is a monotreme and lays eggs (correct).
- **Whale**: This is a placental mammal (incorrect).

**Hint**: Check each option against the characteristics of the groups to find the correct answer.

4. **Conclusion**:
- The only mammal from the provided options that lays eggs is the **duck-billed platypus**.

**Final Answer**: Duck-billed platypus.

### Summary of Steps:
1. Understand mammal classification.
2. Identify characteristics of each group.
3. Evaluate the options based on these characteristics.
4. Conclude with the correct answer.