Malpighian tubules are a part of

Options

A. circulatory system
B. respiratory system
C. excetory system
D. digestive system

Answer

**Step-by-Step Solution:**

1. **Identify the Structures**: Begin by recognizing what Malpighian tubules are. They are specialized structures found in certain organisms.

2. **Determine the Phylum**: Understand that Malpighian tubules are present in organisms belonging to the phylum Arthropoda. This phylum includes insects, arachnids, and crustaceans.

3. **Function of Malpighian Tubules**: Know the primary function of Malpighian tubules. They are responsible for the excretion of waste materials from the body.

4. **Analyze the Options**: Look at the provided options:
- Option A: Circulatory system
- Option B: Respiratory system
- Option C: Excretory system
- Option D: Digestive system

5. **Select the Correct Option**: Since Malpighian tubules are involved in waste excretion, the correct answer is Option C: Excretory system.

6. **Conclusion**: Therefore, Malpighian tubules are a part of the excretory system.

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