Colour of Brown Hydra is due to

Options

A. Chromoplasts
B. Zooxanthellae
C. Zoochlorellae
D. Both A and B.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the reason for the brown color of the Brown Hydra.

2. **Identifying the Options**: The options provided are:
- A) Chromoplast
- B) Zooxanthellae
- C) Both A and B

3. **Analyzing Brown Hydra**: Brown Hydra is known for its brown coloration. This coloration is not due to pigments found in the hydra itself but rather due to a symbiotic relationship with certain algae.

4. **Symbiotic Relationship**: The Brown Hydra lives in a symbiotic association with a type of algae known as zooxanthellae. This relationship benefits both the hydra and the algae.

5. **Role of Zooxanthellae**: The zooxanthellae, which are brown algae, contain pigments that impart the brown color to the hydra. This is the primary reason for the hydra's coloration.

6. **Evaluating the Options**:
- **Chromoplast**: These are colored pigments found in plants, but they are not responsible for the coloration of Brown Hydra. Thus, this option is incorrect.
- **Zooxanthellae**: This is the correct answer as it directly relates to the brown coloration of the Brown Hydra.
- **Both A and B**: Since option A is incorrect, this option is also incorrect.

7. **Conclusion**: The color of Brown Hydra is due to the presence of zooxanthellae.

**Final Answer**: The color of Brown Hydra is due to **Zooxanthellae**.

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