Which one of the following statements is incorrect?

Options

A. Birds and land snails are uricotelic animals
B. Mammals and frogs are ureotelic animals
C. Aquatic amphibians and aquatic insects are ammonotelic animals
D. Birds and reptiles are ureotelic.

Explanation

To determine which statement is incorrect regarding the nitrogenous waste excretion in different animals, we will analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Understanding Nitrogenous Wastes**:
- There are three main types of nitrogenous wastes produced by animals: ammonia, urea, and uric acid.
- Ammonia is highly toxic and requires a large amount of water for excretion.
- Urea is less toxic than ammonia and requires a moderate amount of water for excretion.
- Uric acid is the least toxic and requires the least amount of water for excretion.

2. **Analyzing the Statements**:
- **Statement 1**: "Birds and land snails are uricotelic."
- This is correct. Both birds and land snails excrete uric acid, which requires minimal water.

- **Statement 2**: "Mammals and frogs are ureotelic."
- This is also correct. Mammals and frogs primarily excrete urea, which is moderately toxic and requires a moderate amount of water.

- **Statement 3**: "Aquatic amphibians and aquatic insects are ammonotelic."
- This statement is correct as well. Aquatic animals, including amphibians and insects, typically excrete ammonia due to their aquatic environment, which allows for the dilution of this toxic waste.

- **Statement 4**: "Birds and reptiles are ureotelic."
- This statement is incorrect. Birds and reptiles are uricotelic, meaning they excrete uric acid, not urea.

3. **Conclusion**:
- The incorrect statement among the options provided is: "Birds and reptiles are ureotelic."

### Final Answer:
The incorrect statement is: "Birds and reptiles are ureotelic."

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