Cyanobacteria are also referred to as

Options

A. Golden algae
B. Blue-green algae
C. Protists
D. Slime Moulds.

Explanation

**Step-by-Step Solution:**

1. **Understanding Cyanobacteria**: Begin by recognizing that cyanobacteria are a type of bacteria that can photosynthesize and are often found in aquatic environments. They are known for their blue-green color.

2. **Alternative Name**: Identify the alternative name for cyanobacteria. They are commonly referred to as "blue-green algae" (BGA). This term reflects their color and their historical classification as algae, despite being prokaryotic organisms.

3. **Examples of Cyanobacteria**: Mention specific examples of cyanobacteria, such as Nostoc and Anabaena. These organisms are significant for their ability to fix nitrogen, which is crucial for soil fertility and ecosystem health.

4. **Elimination of Incorrect Options**: If presented with multiple-choice options, eliminate those that do not accurately describe cyanobacteria. For instance:
- Golden algae (not cyanobacteria)
- Protists (not a correct classification for cyanobacteria)
- Slime molds (also not cyanobacteria)

5. **Conclusion**: Conclude that the correct alternative name for cyanobacteria is "blue-green algae."

**Final Answer**: Cyanobacteria are also referred to as "blue-green algae" (BGA).

---