The pigment which protects earthworm from UV rays 

Options

A. Haemoglobin
B. Chlorocruorin
C. Vanadium chromogen
D. Porphyrin

Answer

To answer the question about the pigment that protects earthworms from UV rays, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Options**: The options provided are hemoglobin, chlorochlorin, vanadium chromogen, and porphyrin.

2. **Analyze Hemoglobin**: Hemoglobin is a pigment found in higher animals and is primarily responsible for transporting oxygen in the blood. Since earthworms are not higher animals and hemoglobin does not provide UV protection, this option can be eliminated.

3. **Analyze Chlorochlorin**: Chlorochlorin is similar to chlorophyll and is involved in oxygen transport in certain organisms like some marine invertebrates. Since it also does not serve the purpose of UV protection in earthworms, this option can be eliminated as well.

4. **Analyze Vanadium Chromogen**: Vanadium chromogen is not known to play a role in UV protection in earthworms. Therefore, this option can also be eliminated.

5. **Analyze Porphyrin**: Porphyrin is a dark brown pigment found in earthworms. It is known to protect earthworms from harmful UV rays. This pigment absorbs UV radiation, thereby providing a protective function.

6. **Conclusion**: Based on the analysis, the correct answer is porphyrin, as it is the pigment that protects earthworms from UV rays.

### Final Answer:
The pigment which protects earthworm from UV rays is **porphyrin**.

---