Ceratium is

Options

A. Dinoflagellate
B. Diatom
C. Slime Mould
D. Sporozoan.

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about "Ceratium." We need to determine what type of organism it is.

2. **Options Provided**: The options given are:
- 1st option: Dinoflagellate
- 2nd option: Diatom
- 3rd option: Slime mold
- 4th option: Sporozone

3. **Understanding Ceratium**: Ceratium is known to be a single-celled organism. It is characterized by having two unequal flagella, which is a defining feature of dinoflagellates.

4. **Analyzing the Options**:
- **Diatom**: This group belongs to the class of organisms known as chrysophytes and is not characterized by having two unequal flagella.
- **Slime Mold**: While slime molds are part of the kingdom Protista, they do not fit the characteristics of Ceratium.
- **Sporozone**: This term refers to organisms that have spores in their infective state, such as Plasmodium, but it does not apply to Ceratium.

5. **Conclusion**: Based on the characteristics of Ceratium and the analysis of the options, the correct answer is that Ceratium is a **Dinoflagellate**.

**Final Answer**: Ceratium is a Dinoflagellate (Option 1).

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