The Cyanobacteria of great nutritional value being marketed today is

Options

A. Serytonema
B. Spirogyra
C. Spirulina
D. Stigonema

Answer

**Step-by-Step Solution:**

1. **Understanding Cyanobacteria**: Begin by recognizing that cyanobacteria are often referred to as blue-green algae. They are a group of photosynthetic bacteria that play an important role in ecosystems and can be found in a variety of environments.

2. **Classification**: Identify that cyanobacteria belong to the kingdom Monera. This kingdom includes prokaryotic organisms, which means they do not have membrane-bound organelles such as chloroplasts or mitochondria.

3. **Nutritional Value**: Among the various types of cyanobacteria, focus on their nutritional value. Some cyanobacteria are known for their high nutrient content and are marketed as dietary supplements.

4. **Identifying Spirulina**: Among the options provided (serotonema, spirulina, and stegonema), recognize that spirulina is a well-known type of cyanobacteria that is marketed for its nutritional benefits. It is spiral-shaped and is often referred to as a superfood.

5. **Conclusion**: Based on the information gathered, conclude that the cyanobacteria of great nutritional value being marketed today is **spirulina**. It is recognized as one of the most nutrient-rich foods available and is often promoted for its health benefits.

**Final Answer**: Spirulina

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