Members of which algal class impart red colour to red sea

Options

A. Cyanophyceae
B. Rhodophyceae
C. Phaeophyceae
D. Bacillariophyceae.

Answer

### Step-by-Step Solution:

1. **Identify the Question**: The question asks which algal class is responsible for imparting a red color to the Red Sea.

2. **Understand the Options**: The options provided are:
- Cyanophyce
- Rhodophyce
- Phaeophyce
- Bacillophyce

3. **Research the Red Sea**: The Red Sea is known for its high salinity and unique ecological characteristics. It is important to understand what contributes to its name.

4. **Identify the Key Organism**: The red color of the Red Sea is primarily due to the presence of a specific type of cyanobacteria known as **Trichodesmium**. This organism is a type of cyanophyce.

5. **Connect the Organism to the Algal Class**: Since Trichodesmium belongs to the cyanophyce class, it indicates that this class is responsible for the red coloration observed in the Red Sea.

6. **Conclude with the Correct Answer**: Based on the information gathered, the correct answer to the question is **Cyanophyce**.

### Final Answer:
The members of the algal class that impart red color to the Red Sea are **Cyanophyce**.

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