………… and ………… are egg-laying mammals.

Explanation

**Step-by-Step Solution:**

1. **Understanding Egg-Laying Mammals**: Egg-laying mammals are a unique group of mammals that do not give live birth but instead lay eggs. This characteristic distinguishes them from most other mammals.

2. **Identifying the Order**: These egg-laying mammals belong to a specific order known as Monotremata. This order is significant as it represents a transitional form between reptiles and mammals.

3. **Recognizing the Characteristics**: Monotremata exhibits features of both reptiles and mammals. For instance, they lay eggs (a characteristic of reptiles) but also possess mammary glands and have a hairy body (characteristics of mammals).

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