Usually plant body of brown algae consists of -

Options

A. Hold fast
B. Stipe
C. Frond
D. All

Answer

To answer the question about the usual plant body structure of brown algae, we can break down the components as follows:

1. **Understanding Brown Algae**: Brown algae belong to the group of algae characterized by their brown pigments, primarily due to the presence of fucoxanthin. They are typically found in marine environments.

2. **Key Structures of Brown Algae**:
- **Holdfast**: This structure anchors the brown algae to the substrate (the surface it grows on). It does not absorb nutrients but provides stability.
- **Stipe**: This is the stalk-like structure that supports the fronds. It acts like a stem in higher plants, providing support and structure.
- **Frond**: The frond is the leaf-like structure where photosynthesis occurs. It is responsible for capturing sunlight and converting it into energy for the plant.

3. **Storage and Pigments**: Brown algae contain chlorophylls A and C for photosynthesis and store food in the form of mannitol and laminarin.

4. **Conclusion**: The typical plant body of brown algae consists of all three components: holdfast, stipe, and frond. Therefore, the correct answer to the question is "all."

### Final Answer:
The usual plant body of brown algae consists of holdfast, stipe, and frond.