Procaryotic algae are

Options

A. Phycomyceae
B. Myxophyceae
C. Cyanobacteria
D. Both B and C.

Answer

**Step-by-Step Solution:**

1. **Understanding Prokaryotic Algae**:
- Prokaryotic algae are organisms that lack a true nucleus and membrane-bound organelles. This means they do not have structures like mitochondria, chloroplasts, or the endoplasmic reticulum.

2. **Identifying Prokaryotic Algae**:
- Prokaryotic algae are commonly referred to as cyanobacteria, also known as blue-green algae. Despite the name "algae," they are classified as bacteria due to their prokaryotic nature.

3. **Analyzing the Options**:
- Option A: Phycomycetes - This group belongs to the kingdom Fungi and is eukaryotic, making it an incorrect choice.
- Option B: Myxomycetes - These are slime molds that belong to the kingdom Protista and are also eukaryotic, thus incorrect.
- Option C: Cyanobacteria - This is the correct answer as it represents prokaryotic algae.
- Option D: Both B and C - Since B is incorrect, this option is also incorrect.

4. **Conclusion**:
- The only correct answer is **Cyanobacteria**. Therefore, the answer to the question "Prokaryotic algae are" is **Cyanobacteria**.

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