Kelps are

Options

A. (a) fresh water algae
B. (b) marine green algae
C. (c) large marine parenchymatous brown algae
D. (d) large marine parenchymatous and algae.

Answer

**Step-by-Step Solution:**

1. **Identify the Group:** The question asks about kelps. The first step is to determine which group of algae they belong to.

2. **Classification of Algae:** Kelps are classified as brown algae. This classification is crucial as it helps us understand their characteristics and habitat.

3. **Habitat:** Next, we note that kelps are found in marine habitats. This means they thrive in oceanic environments, which is important for their growth and survival.

4. **Appearance:** Kelps are often referred to as "underwater forests" because of their large size and the way they grow. They can create dense underwater structures that resemble forests.

5. **Size:** It’s important to highlight that kelps are very large in size compared to other types of algae. This characteristic sets them apart and contributes to their forest-like appearance.

6. **Tissue Structure:** Kelps have parenchymatous tissue, which superficially resembles parenchyma tissue found in higher plants. However, they are not classified as true parenchyma since they are among the simplest forms of plant life.

7. **Conclusion:** Based on the above points, we conclude that kelps are classified as large marine parenchymatous brown algae. Therefore, the correct answer is option C.

**Final Answer:** C) Large marine parenchymatous brown algae.

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