Sweat glands and external ears are characters of group

Options

A. Birds
B. Amphibians
C. Reptiles
D. Mammals.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which group of animals possesses sweat glands and external ears.

2. **Identifying the Options**: The options provided are birds, amphibians, reptiles, and mammals.

3. **Analyzing Each Group**:
- **Birds**: Birds do not have external ears and lack sweat glands. They have feathers that help with thermoregulation but do not produce sweat.
- **Amphibians**: Amphibians do not have sweat glands or external ears. They rely on their skin for moisture and do not have a thermoregulatory mechanism like mammals.
- **Reptiles**: Reptiles also lack sweat glands and external ears. They have structures that may resemble ears but do not function like the external ears of mammals.
- **Mammals**: Mammals are characterized by the presence of sweat glands and external ears. Sweat glands are important for thermoregulation and excretion, which are essential for maintaining body temperature and removing waste.

4. **Conclusion**: Based on the analysis, the correct answer is mammals, as they are the only group among the options that possess both sweat glands and external ears.

**Final Answer**: Mammals

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