Chlorella is a type of algae that grows in fresh water and is used to make nutritional supplements and medicine.So the option is B( chlorella).

**Chlorella: A Freshwater Green Alga Rich in Protein**

Chlorella is a freshwater green alga that is known for its high protein content. Let's explore why Chlorella is the correct answer among the options provided.

**What is Chlorella?**
Chlorella is a single-celled green alga that belongs to the division Chlorophyta. It is found in freshwater environments such as ponds, lakes, and rivers. Chlorella is a photosynthetic organism that uses sunlight to convert carbon dioxide and water into organic compounds, including proteins.

**Rich in Protein**
Chlorella is particularly known for its high protein content. In fact, it is one of the richest plant sources of protein available. The protein content in Chlorella can range from 45% to 60% of its dry weight. This makes it an excellent source of dietary protein, especially for vegetarians and vegans who may have limited options for plant-based protein sources.

**Health Benefits**
The high protein content in Chlorella offers several health benefits. Here are some of the key advantages:

1. Muscle Building and Repair: Proteins are essential for building and repairing tissues, including muscles. Chlorella's protein-rich composition makes it a valuable dietary addition for athletes, bodybuilders, and individuals looking to enhance muscle growth and recovery.

2. Weight Management: Protein-rich foods help increase satiety and reduce hunger, making it easier to control calorie intake and manage weight. Chlorella's protein content can contribute to a feeling of fullness, potentially aiding in weight management.

3. Nutrient Profile: Chlorella is not only rich in protein but also contains various essential nutrients. It is a good source of vitamins, minerals, antioxidants, and omega-3 fatty acids, which are important for overall health and well-being.

4. Detoxification: Chlorella has been studied for its potential detoxifying properties. It is believed to bind to heavy metals and other toxins in the body, aiding their removal through the digestive system.

**Conclusion**
In conclusion, Chlorella is a freshwater green alga that is rich in protein. Its high protein content, along with its various health benefits and nutrient profile, makes it a valuable dietary supplement for individuals seeking plant-based protein sources.