Agar-agar is commercially obtained form

Options

A. green algae
B. blue-green algae
C. brown algae
D. red algae.

Explanation

**Step-by-Step Solution:**

1. **Understanding Agar-Agar**: Begin by recognizing that agar-agar is a gelatinous substance that is widely used in laboratories as a culture medium for growing microbes. It is also commonly used in the food industry, particularly in the production of jellies and ice creams.

2. **Identifying the Source**: Agar-agar is derived from specific types of algae. It is essential to know which type of algae is the source of agar-agar.

3. **Types of Algae**: There are three main types of algae mentioned:
- Green algae
- Blue-green algae
- Brown algae
- Red algae

4. **Determining the Correct Type**: Among these, agar-agar is specifically obtained from red algae. This is a crucial point as it distinguishes red algae from the other types.

5. **Conclusion**: Therefore, the correct answer to the question "Agar-agar is commercially obtained from" is red algae.

**Final Answer**: Agar-agar is commercially obtained from red algae.

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