Birds are

Options

A. Uricotelic
B. Ureotelic
C. Ammonotelic
D. Aminotelic

Answer

### Step-by-Step Solution:

1. **Understanding Nitrogenous Waste Excretion**:
- Birds excrete nitrogenous waste, which is a byproduct of protein metabolism. The form in which this waste is excreted varies among different animal groups.

2. **Identifying the Excretion Methods**:
- There are three primary methods of nitrogenous waste excretion:
- **Uricotelic**: Excretion of waste in the form of uric acid.
- **Ureotelic**: Excretion of waste in the form of urea.
- **Ammonotelic**: Excretion of waste in the form of ammonia.

3. **Birds as Uricotelic Animals**:
- Birds are classified as uricotelic because they excrete nitrogenous waste primarily in the form of uric acid. This is advantageous for birds as uric acid is less toxic and requires less water for excretion compared to urea or ammonia.

4. **Reasons for Uric Acid Excretion**:
- The excretion of uric acid helps birds minimize their body weight, which is crucial for flight. Uric acid is less soluble in water, allowing birds to conserve water and reduce the weight of their waste.

5. **Conclusion**:
- Therefore, the correct classification for birds regarding their method of excretion is uricotelic.

### Final Answer:
Birds are uricotelic, meaning they excrete nitrogenous waste in the form of uric acid.

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