Animals which are at metabolic advantage are

Options

A. Aquatic
B. Ectothermal
C. Endothermal
D. Both A and B.

Answer

To solve the question "Animals which are at metabolic advantage are," let's analyze the options provided and understand the characteristics of each type of animal mentioned.

### Step-by-Step Solution:

1. **Understanding the Options**:
- **Option A: Aquatic** - These are animals that live in water. While they have adaptations for their environment, they are not specifically known for metabolic advantages related to temperature regulation.
- **Option B: Ectothermal** - Ectothermal animals, also known as cold-blooded animals, rely on external sources of heat to regulate their body temperature. They do not have a metabolic advantage in maintaining a stable internal temperature.
- **Option C: Endothermal** - Endothermal animals, or warm-blooded animals, can regulate their body temperature internally through metabolic processes. This allows them to maintain a stable internal environment regardless of external conditions, giving them a metabolic advantage.
- **Option D: Both A and B** - This option suggests that both aquatic and ectothermal animals have a metabolic advantage, which is incorrect based on the definitions provided.

2. **Identifying the Correct Answer**:
- Based on the definitions and characteristics, endothermal animals (Option C) are the ones that have a metabolic advantage because they can maintain their body temperature through metabolic activity. This is crucial for their survival and functioning in various environments.

3. **Conclusion**:
- The correct answer to the question is **Option C: Endothermal**.

### Final Answer:
The animals which are at metabolic advantage are **endothermal animals** (Option C).

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