Tetrasporophyte is found in

Options

A. Laminaria
B. Ulva
C. Gelidium
D. Sargassum.

Answer

**Step-by-Step Solution:**

1. **Understanding Tetrasporophyte**: The tetrasporophyte is a diploid phase in the life cycle of certain algae, specifically in the group known as Rhodophyta (red algae). It is important to recognize that this structure produces tetraspores through a process called meiosis.

2. **Identifying the Options**: The question provides four options: Laminaria, Alva, Gelidium, and Sargassum. We need to determine which of these options contains the tetrasporophyte.

3. **Analyzing Each Option**:
- **Laminaria**: This is classified as brown algae (Phaeophyta). Brown algae do not have a tetrasporophyte stage.
- **Alva**: This is a type of green algae (Chlorophyta). Green algae also do not produce tetrasporophytes.
- **Gelidium**: This is a red algae (Rhodophyta) and is known to have a tetrasporophyte stage that produces tetraspores.
- **Sargassum**: This is another brown algae, which similarly does not have a tetrasporophyte stage.

4. **Conclusion**: Since Gelidium is the only option that belongs to the red algae group and possesses a tetrasporophyte stage, it is the correct answer.

5. **Final Answer**: Tetrasporophyte is found in **Gelidium**.

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