Aquatic animals like fish excrete their wastes in gaseous form as

Options

A. Oxygen
B. Hydrogen
C. Ammonia
D. Nitrogen

Explanation

**Step-by-Step Solution:**

1. **Understanding Excretion**: Excretion is the process by which animals eliminate waste products from their bodies. These waste products can be toxic and need to be removed to maintain health.

2. **Types of Waste Products**: Different animals excrete different types of waste based on their environment. For example, humans excrete urea in urine, while aquatic animals have different methods due to their habitat.

3. **Aquatic Animals and Waste Excretion**: Aquatic animals, such as fish, live in water and have a unique way of excreting waste. They can afford to excrete waste in a gaseous form because the water around them can dissolve these gases.

4. **Identifying the Waste Product**: Among the options given:
- **Oxygen**: This is not a waste product; it is essential for respiration.
- **Hydrogen**: This is not typically excreted as waste.
- **Ammonia**: This is a toxic waste product that aquatic animals excrete in gaseous form. It dissolves easily in water.
- **Nitrogen**: While nitrogen is a component of ammonia, it is not the form in which aquatic animals excrete waste.

5. **Conclusion**: Based on the above points, the correct answer is that aquatic animals like fish excrete their waste in the form of **ammonia**.

**Final Answer**: Aquatic animals like fish excrete their wastes in gaseous form as **ammonia**.

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