Complex post fertilization development is seen in which algae :-

Options

A. Green algae
B. Brown algae
C. Yellow algae
D. Red algae

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which type of algae exhibits complex post-fertilization development.

2. **Identifying the Options**: The options provided are:
- Green algae
- Brown algae
- Yellow algae
- Red algae

3. **Analyzing Each Option**:
- **Green Algae**: Generally have simpler life cycles and do not exhibit complex post-fertilization development.
- **Brown Algae**: While they have a complex life cycle, their post-fertilization processes are not as intricate as those of red algae.
- **Yellow Algae**: This group is less studied and does not typically show complex post-fertilization development.
- **Red Algae**: Known for their complex life cycles and advanced reproductive strategies.

4. **Focusing on Red Algae**: Red algae, also known as Rhodophyta, are primarily found in marine environments and exhibit complex post-fertilization development. They have an advanced oogamous type of sexual reproduction where:
- Male gametes are non-motile.
- Female reproductive structures are called carpogonia.
- Fertilization occurs with the help of water currents.

5. **Post-Fertilization Development**: In red algae, the post-fertilization changes are complex and lead to a triphasic life cycle, which includes different phases of development.

6. **Conclusion**: Based on the analysis, the correct answer is **Red Algae**.

**Final Answer**: The complex post-fertilization development is seen in **Red Algae**.

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