Euglena is a

Options

A. Ciliate
B. Sporozoan
C. Flagellate
D. Sarcodine.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what type of organism Euglena is classified as among the given options: ciliate, sporozoan, flagellate, or sarcoidin.

2. **Classification of Protozoans**: Protozoans are classified based on their locomotory structures. The four main classes are:
- Ciliates: Organisms that have cilia for movement.
- Sporozoans: Organisms that do not have any locomotory structures and are often parasitic.
- Flagellates: Organisms that have flagella for movement.
- Sarcodines: Organisms that use pseudopodia for movement.

3. **Analyzing Euglena**: Euglena is known to have a long flagellum, which is a whip-like structure used for locomotion. This characteristic aligns with the classification of flagellates.

4. **Identifying the Correct Option**: Since Euglena possesses a flagellum for movement, it falls under the category of flagellates. Therefore, the correct answer to the question is "flagellate."

**Final Answer**: Euglena is a flagellate.

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