Which one is a red alga

Options

A. Gelidium
B. Chlorella
C. Volvox
D. Ulothrix.

Answer

To determine which one is a red alga from the given options, we can follow these steps:

### Step 1: Understand the Classification of Algae
Algae are classified into three main categories based on their pigments:
- Red Algae (Rhodophyta)
- Brown Algae (Phaeophyta)
- Green Algae (Chlorophyta)

### Step 2: Analyze the Given Options
We have four options to consider:
1. Gelidium
2. Chlorella
3. Volvox
4. Eulothrix

### Step 3: Identify Each Option
- **Gelidium**: This is known to be a red alga.
- **Chlorella**: This is a type of green alga.
- **Volvox**: This is also a green alga.
- **Eulothrix**: This is another example of a green alga.

### Step 4: Conclusion
From the analysis, only **Gelidium** is classified as a red alga. The other options (Chlorella, Volvox, and Eulothrix) are all green algae.

### Final Answer
The correct answer is **Gelidium**.

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