Excretory organ of Crab is

Options

A. Nephridium
B. Flame cell
C. Coxal gland
D. Malpighian tube.

Answer

To determine the excretory organ of a crab, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Classification of Crab**:
- Crabs belong to the phylum Arthropoda and the class Crustacea. This classification is essential to understand their biological features.

2. **Understand the Excretory Systems in Different Phyla**:
- Different organisms have different excretory systems. For example:
- **Nephridia** are found in phylum Annelida.
- **Flame cells** are characteristic of phylum Platyhelminthes.
- **Malpighian tubules** are present in some arthropods, but not specifically in crabs.
- **Coxal glands** are specific to certain crustaceans, including crabs.

3. **Focus on the Excretory Organ of Crabs**:
- Among the options provided (nephridium, flame cells, coxal glands, and malpighian tubules), we need to identify which one is associated with crabs.
- Crabs utilize **coxal glands** for excretion. These glands help in the removal of waste products from their bodies.

4. **Conclusion**:
- Therefore, the correct answer to the question "Excretory organ of Crab is" is **Coxal gland**.

### Final Answer:
The excretory organ of a crab is the **Coxal gland**.

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