Algae are important, we should study algae because

Options

A. They are good experimental materials
B. They may become important constituent of future food for human beings
C. They can be easily grown in water tanks
D. They renew oxygen of atmosphere and water.

Answer

**Step-by-Step Solution:**

1. **Understanding Algae**: Algae are photosynthetic eukaryotes that play a crucial role in aquatic ecosystems. They are primary producers, meaning they convert sunlight into energy, forming the base of the aquatic food chain.

2. **Evaluating the Importance of Algae**: Algae have several significant roles, including:
- Serving as a source of food for various organisms in aquatic environments.
- Contributing to oxygen production in water through photosynthesis.
- Being a potential food source for humans in the future due to their high nutritional value.

3. **Analyzing the Options**:
- **Option A**: "They are good experimental materials." This is not the best choice, as many other organisms are also used in experiments.
- **Option B**: "They may become an important constituent of future food for human beings." This is a strong option because of their nutritional benefits and potential to address food shortages.
- **Option C**: "They can be easily grown in water tanks." This option is misleading, as other pathogens can also grow in the same conditions, making it less specific to algae.
- **Option D**: "They renew oxygen of atmosphere and water." While algae do contribute to oxygen production, they are not the only organisms responsible for this process.

4. **Conclusion**: After evaluating all the options, the most appropriate answer is **Option B**: "They may become an important constituent of future food for human beings." This highlights their potential role in addressing future food security.

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