The major excretory product of arthropods is

Options

A. Ammonia
B. Urea
C. Uric acid
D. Trimethylamine oxide.

Answer

To determine the major excretory product of arthropods, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Phylum Arthropoda**:
- Arthropods include a diverse group of animals such as insects, crustaceans, arachnids, etc. Each of these groups may have different methods of excretion based on their habitat and physiology.

2. **Identify Excretory Products**:
- The common excretory products in animals are ammonia, urea, and uric acid. Each of these is excreted by different groups of organisms based on their environment and metabolic processes.

3. **Examine the Options**:
- **Ammonia**: This is primarily excreted by aquatic organisms, including some crustaceans. However, it is not the major excretory product for most arthropods.
- **Urea**: This is the main excretory product in mammals and is not typical for arthropods.
- **Uric Acid**: Many terrestrial arthropods, such as insects, excrete uric acid as their primary nitrogenous waste. This is because uric acid is less toxic and conserves water, which is advantageous for land-dwelling organisms.
- **Trimethylamine oxide**: This is not a common excretory product in arthropods.

4. **Conclusion**:
- Based on the information, the major excretory product of arthropods is **uric acid**. This is because most arthropods are uricotelic, meaning they primarily excrete uric acid.

### Final Answer:
The major excretory product of arthropods is **uric acid**.

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