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

Answer

**Step-by-Step Solution:**

1. **Understanding the Terms:**
- Uricotelic animals excrete nitrogenous waste in the form of uric acid.
- Ureotelic animals excrete nitrogenous waste in the form of urea.
- Ammonotelic animals excrete nitrogenous waste in the form of ammonia.

2. **Analyzing the Statements:**
- **Statement 1:** "Birds and land snails are uricotelic animals."
- This is correct. Birds and land snails do excrete uric acid.

- **Statement 2:** "Frogs and mammals are ureotelic."
- This is also correct. Frogs (as terrestrial amphibians) and mammals excrete urea.

- **Statement 3:** "Aquatic amphibians and aquatic insects are ammonotelic."
- This is correct as well. Aquatic amphibians and aquatic insects excrete ammonia.

- **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 Statement 4. Therefore, the answer is that Statement 4 is incorrect.

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

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