Normally algae show a haplontic life cycle. Polysiphonia and fucus
are exceptions to this rule. The correct option depicting their classes and life cycles is.

Options

A. Polysiphonia is a green algae with haplo diplontic life cycle and
Fucus is a red alga with diplontic life cycle
B. Polysiphonia is a green algae with diplontic life cycle and
Fucus is a red alga with haplo- diplontic life cycle
C. Polysiphonia is a red algae with haplo diplontic life cycle and
Fucus is a brown alga with diplontic life cycle
D. Polysiphonia is a red algae with diplontic life cycle and
Fucus is a brown alga with haplo- diplontic life cycle

Answer

To solve the question regarding the life cycles of Polysiphonia and Fucus, we will analyze the statements provided and identify the correct one based on our knowledge of algae classifications and their life cycles.

### Step-by-Step Solution:

1. **Understanding Algal Life Cycles**:
- Algae typically exhibit a haplontic life cycle, where the dominant stage is haploid (n) and the diploid (2n) stage is short-lived.
- However, there are exceptions to this rule, such as Polysiphonia and Fucus.

2. **Identifying the Classes of Algae**:
- **Polysiphonia**: This is a type of red algae, classified under the Rhodophyta.
- **Fucus**: This is a brown algae, classified under the Phaeophyceae.

3. **Determining Their Life Cycles**:
- **Polysiphonia** exhibits a haplodeplontic life cycle, which includes both haploid and diploid stages but is primarily haploid.
- **Fucus** exhibits a diplontic life cycle, where the diploid stage is dominant and the haploid stage is reduced.

4. **Analyzing the Statements**:
- **Statement A**: "Polysiphonia is a green algae with haplodeplontic life cycle and Fucus is a red alga with diplontic life cycle."
- Incorrect: Polysiphonia is red, not green, and Fucus is brown, not red.
- **Statement B**: "Polysiphonia is a green algae with diplontic life cycle and Fucus is a red alga with haplodeplontic life cycle."
- Incorrect: Both classifications of algae are wrong.
- **Statement C**: "Polysiphonia is a red algae with haplodeplontic life cycle and Fucus is a brown algae with diplontic life cycle."
- Correct: This accurately describes both algae and their life cycles.
- **Statement D**: "Polysiphonia is a red algae with diplontic life cycle and Fucus is a brown alga with haplodeplontic life cycle."
- Incorrect: Polysiphonia has a haplodeplontic life cycle, not diplontic.

5. **Conclusion**:
- The correct answer is **Statement C**: "Polysiphonia is a red algae with haplodeplontic life cycle and Fucus is a brown algae with diplontic life cycle."