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 crustaceans are ammonotelic animals.
D. Birds and reptiles are ureotelic .

Answer

To determine which statement is incorrect, we will analyze each of the four statements provided in the question.

### Step 1: Analyze Statement 1
**Statement 1:** "Bird and land snail are uricotelic animals."
- **Explanation:** Uricotelic animals excrete nitrogenous waste primarily in the form of uric acid. Birds and land snails do indeed excrete uric acid, which allows them to conserve water. This statement is **correct**.

### Step 2: Analyze Statement 2
**Statement 2:** "Mammals and frog are ureotelic animals."
- **Explanation:** Ureotelic animals excrete nitrogenous waste mainly as urea. Mammals and frogs (which are amphibians) do excrete urea. Thus, this statement is also **correct**.

### Step 3: Analyze Statement 3
**Statement 3:** "Aquatic amphibian and crustaceans are ammonotelic animals."
- **Explanation:** Ammonotelic animals excrete ammonia as their primary nitrogenous waste. Aquatic amphibians (like frogs) and crustaceans do excrete ammonia, especially in aquatic environments where water is abundant. This statement is **correct**.

### Step 4: Analyze Statement 4
**Statement 4:** "Bird and reptiles are ureotelic."
- **Explanation:** This statement claims that birds and reptiles excrete urea. However, birds and most reptiles are actually uricotelic, meaning they excrete uric acid, not urea. Therefore, this statement is **incorrect**.

### Conclusion
The incorrect statement among the four provided is **Statement 4**: "Bird and reptiles are ureotelic."

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