One of the following excrete urea

Options

A. Snakes
B. Birds
C. Insects
D. None

Answer

To solve the question "One of the following excretes urea," we need to understand the different types of nitrogenous waste products and the organisms that excrete them. Here’s a step-by-step breakdown:

### Step 1: Identify the Types of Nitrogenous Wastes
- There are three primary types of nitrogenous waste products:
1. Urea
2. Uric Acid
3. Ammonia

### Step 2: Understand the Characteristics of Each Waste
- **Ammonia**:
- Highly toxic and requires a large amount of water for excretion.
- Commonly excreted by aquatic animals (like fish) because they have access to abundant water.

- **Urea**:
- Less toxic than ammonia and requires less water for excretion.
- Typically excreted by terrestrial animals, some amphibians, and mammals.

- **Uric Acid**:
- Least toxic and requires very little water for excretion.
- Commonly excreted by birds, insects, and reptiles.

### Step 3: Determine Which Organisms Excrete Urea
- Since urea is excreted by terrestrial animals, mammals, and some amphibians, we can conclude that if the question provides options, we should look for any of these types of organisms.

### Step 4: Select the Correct Answer
- If the options include mammals or terrestrial animals, they would be the correct answer as they excrete urea.

### Conclusion
- The answer to the question "One of the following excretes urea" would be any organism that is a mammal or a terrestrial animal.

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